KR101744493B1 - Binder resin for nonaqueous secondary battery electrode, binder resin composition for nonaqueous secondary battery electrode, slurry composition for nonaqueous secondary battery electrode, electrode for nonaqueous secondary battery, and nonaqueous secondary battery - Google Patents

Abstract

[화학식 22]

When the binder resin for a nonaqueous secondary battery electrode of the present invention is dissolved in water to prepare a solution having a concentration of 5 mass% and particle size distribution measurement is performed at 25 캜 by dynamic light scattering method, I _S ≥ 30 (I _S is 1 Represents the sum of the scattering intensities observed in a particle diameter range of ~ 100 nm). The binder resin for a non-aqueous secondary battery electrode of the present invention contains a polymer (B) having a structural unit represented by the following general formula (11) and a specific structural unit. The binder resin for a nonaqueous secondary battery electrode of the present invention may further comprise a polymer (?) Having a specific structural unit and a structural unit represented by the following general formula (22) and / or a polymer (? And a polymer (b2) having a structural unit to be displayed.
(11)

[Chemical Formula 22]

Description

TECHNICAL FIELD [0001] The present invention relates to a binder resin for a non-aqueous secondary battery electrode, a binder resin composition for a non-aqueous secondary battery electrode, a slurry composition for a non-aqueous secondary battery electrode, an electrode for a non-aqueous secondary battery, and a non-aqueous secondary battery ELECTRODE, SLURRY COMPOSITION FOR NONAQUEOUS SECONDARY BATTERY ELECTRODE, ELECTRODE FOR NONAQUEOUS SECONDARY BATTERY, AND NONAQUEOUS SECONDARY BATTERY}

The present invention relates to a binder resin for a nonaqueous secondary battery electrode, a binder resin composition for a nonaqueous secondary battery electrode, a slurry composition for a nonaqueous secondary battery electrode, an electrode for a nonaqueous secondary battery, and a nonaqueous secondary battery.

The present application is based on Japanese Patent Application No. 2011-265040 filed on December 2, 2011, Patent Application No. 2012-39952 filed on February 27, 2012, and Japanese Patent Application filed on April 13, 2012 Which is incorporated herein by reference, and its contents are hereby incorporated herein by reference.

BACKGROUND ART [0002] A secondary battery is used as a battery for portable electronic appliances such as a notebook computer or a mobile phone, or as a battery for a hybrid car or an electric car. In these applications, lithium ion secondary batteries, which are a kind of non-aqueous secondary batteries (non-aqueous electrolyte secondary batteries), have been used as secondary batteries because of their high energy density.

Generally, as the electrode of the non-aqueous secondary battery, a collector including a metal foil or the like and a mixture layer provided on the collector is used, and the active material and the conductive additive are held by the binder resin in the mixture layer. Such an electrode is usually prepared by kneading an active material, a conductive auxiliary agent, a binder resin, and a liquid medium (solvent) to prepare a slurry composition, applying the slurry composition to one side or both sides of the current collector by a transfer roll or the like, To form a composite layer, and thereafter, if necessary, compression molding with a roll press machine or the like. As the liquid medium, it is used that the active material and the conductive auxiliary agent are dispersed and the binder resin is dissolved.

Conventionally, as a binder resin for a non-aqueous secondary battery electrode, a fluorine resin such as polyvinylidene fluoride (PVDF) is used. PVDF has been widely used because it has advantages such as good rheological characteristics (thixotropy) when used as a slurry composition and electrochemical stability in a negative electrode.

However, since the binder resin such as PVDF is dissolved in an organic solvent such as N-methyl-2-pyrrolidone (NMP) for use in manufacturing the electrode, the solvent recovery cost at the time of drying and the load And the like.

Therefore, in recent years, attempts have been made to replace organic solvents with water, and in the case of a negative electrode, PVDF is dispersed in water to be used in a latex state in many cases. As the binder resin for the negative electrode, an aqueous dispersion binder resin such as styrene-butadiene rubber (SBR) latex or carboxymethyl cellulose (CMC) which is a thickener may be used.

However, there is a problem that PVDF or SBR has a low binding force. Therefore, when PVDF or SBR is used as the binder resin, it is difficult to improve battery performance such as the capacity, rate characteristics, cycle characteristics, and the like of the non-aqueous secondary battery. For example, in order to improve the rate characteristic that affects the ease of electron transfer, an increase in the amount of the conductive additive is effective. In order to increase the amount of the conductive additive in a limited space in the battery, it is necessary to reduce the amount of the binder. However, if the amount of the binder is reduced, the adhesion between the current collector and the mixed layer (adhesion) The composite layer is peeled off from the current collector or the active material is lost from the composite layer, thereby deteriorating the battery performance.

In order to solve such a problem, a method of defining various parameters has been proposed for adhesion to the current collector (tackiness) and the like. For example, Patent Document 1 discloses that a binder having a THF gel content of 5% or less and a binder composition containing an organic solvent containing NMP as a main component has a second virial coefficient measured by a static light scattering method at a specified value or lower And a rotation radius of the polymer is defined within a specific range. Patent Document 2 proposes a method of mixing two kinds of liquid medium dispersion liquid of polymer having a specific particle size of primary particles within a specific range in a specific amount.

In addition, since the water dispersion binder resin is distributed in a state including water, there is a problem that the transportation cost is increased. In addition, since a fungicide is usually added to the binder resin of the water dispersion system for the purpose of inhibiting the generation of fungi, there is a concern that the battery performance is lowered.

Thus, although it is desired to provide a binder resin in the form of powder in the form of a water dispersion binder resin, latex resins often have a low glass transition temperature, and once formed into a powder, the polymer chains become entangled and difficult to be dispersed again in water There was a problem, and supply to powder was difficult.

Therefore, there is a demand for a powdery binder resin that can be used by dissolving or dispersing in water in the production of an electrode so that the PVDF powder is dissolved in NMP.

On the other hand, since CMC is a water-soluble polymer, it can be used by dissolving it in water at the time of electrode production. However, because CMC is derived from natural products, the quality of each supplied lot is not stable, and as a result, the quality of the resulting electrode is also difficult to stabilize.

Therefore, a non-natural and water-soluble binder resin which can be supplied with stable quality is desired.

In addition, it is also required that the binder resin has high battery performance.

To such a problem, a polymer having an N-vinyl acetamide unit as a binder resin has been reported.

For example, Patent Document 3 discloses a resin component comprising a copolymer of poly N-vinyl acetamide and ethylene oxide (EO) and propylene oxide (PO) as a binder resin. According to this binder resin, the binder property, battery characteristics under a low-temperature to room-temperature environment, and conductivity of lithium ion are excellent.

However, since the EO chain or the PO chain has a molecular structure similar to that of the electrolytic solution, the copolymer of EO and PO sometimes elutes into the electrolytic solution, which may adversely affect battery performance.

Patent Document 4 discloses a positive electrode paste for a non-aqueous battery comprising a poly N-vinyl acetamide as a polymer containing a repeating structural unit having an amide structure. It is said that poly N-vinyl acetamide can improve the required performance of a secondary battery (particularly, a non-aqueous secondary battery) such as paste stability, binding property, electrochemical stability and the like. In addition, elution into an electrolytic solution is difficult to occur.

Japanese Patent Application Laid-Open No. 2007-087881 Japanese Patent Application Laid-Open No. 2003-100298 Japanese Patent Application Laid-Open No. 2002-117860 Japanese Patent Application Laid-Open No. 2002-251999

However, in the methods described in Patent Documents 1 and 2 which use a small particle size latex, since the latex of small particle size is butadiene rubber or acrylic rubber and swells in NMP, it is not necessarily sufficient that the slip composition is thermally fired.

 Tic baking of the slurry composition affects the storage stability of the slurry composition and the cell performance. For example, when the slurry composition is poor in tacking, the coating composition does not change at a low point at the time of coating (when shearing stress is applied) so that coating can not be performed satisfactorily, (Such as unevenness due to sedimentation of the active material). As a result, the adhesion (cohesiveness) between the current collector and the mixture layer and the smoothness (uniformity) of the composite layer become poor, and the battery performance is deteriorated.

Further, as described in Patent Document 4, an electrode using poly N-vinyl acetamide composed of only repeating structural units having an amide structure as a binder resin is poor in flexibility.

Disclosure of the Invention The present invention has been made in view of the above circumstances and provides a binder resin for a water-soluble non-aqueous secondary battery electrode, a binder resin composition for a non-aqueous secondary battery electrode, A slurry composition for an electrode, an electrode for a non-aqueous secondary battery, and a non-aqueous secondary battery.

The present invention also provides a binder resin for a water-soluble non-aqueous secondary cell electrode, a binder resin composition for a non-aqueous secondary battery electrode, a slurry composition for a non-aqueous secondary battery electrode, a non-aqueous secondary battery electrode, And to provide the above-mentioned objects.

As a result of various studies, the inventors of the present invention have obtained the following findings.

When the binder resin is measured by the dynamic light scattering method (DLS) when the binder resin is dissolved in water used as a liquid medium in a slurry preparation process at a concentration of 5 mass% It is sometimes possible to measure the particle size distribution even though it is completely dissolved. The sum of the scattering intensities (nanogel strength) observed in the particle size range of 1 to 100 nm as measured by this DLS shows a positive correlation with the tic plasticity of the slurry composition.

As a result of intensive studies, the inventors of the present invention have found that, in addition to an amide monomer derived from an amide structural unit, a polymer obtained by selecting and using monomers having a specific structure and copolymerizing these polymers is excellent in water solubility, ≪ / RTI >

As a result of intensive studies, the present inventors have found that a mixture of a polymer having an amide structural unit and a specific structural unit as a binder resin or a polymer having an amide structural unit and a polymer having a specific structural unit is water- It is possible to form a battery having excellent battery characteristics, and further, the battery is excellent in battery characteristics.

The first aspect of the present invention has the following features.

≪ 1 > A binder resin for a non-aqueous secondary battery electrode used as the binder resin in a slurry composition for a non-aqueous secondary battery electrode containing a binder resin, an active material and water,

The binder resin for a nonaqueous secondary battery electrode, which satisfies the following formula (i) when the binder resin is dissolved in the water to prepare a solution having a concentration of 5% by mass and a particle size distribution measurement is performed at 25 캜 by dynamic light scattering .

I _S ? 30 (i)

(In the formula (i), I _S represents the sum of the scattering intensities observed in a particle diameter range of 1 to 100 nm.)

≪ 2 > The slurry composition for a non-aqueous secondary battery electrode according to any one of the above [1] to [

After the active material and 100 parts by weight of the conductive additive and 5 parts by mass of the art binder resin 2 parts by mass, a mixture of 40 mass parts of water to a slurry composition, while varying the shear rate up to 100sec ^-1 from 0.03sec ^-1 measuring viscoelasticity by a shear rate which program while changing the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, when performing the viscoelasticity measurement at 25 ℃, to, to satisfy the expression (ii) a non-aqueous secondary described in <1> Binder resin for battery electrode.

? _0.1 /? ₈₀ ? 20 (ii)

(Formula (ii) of, η ₀ is _.1 when varying the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity indicates the viscosity at a shear rate of 0.1sec ^-1, η is the shear rate ₈₀ while the change from 100sec ^-1 to 0.03sec ^-1 represents a viscosity at a shear rate of 80sec ^-1, as measured in the visco-elastic).

<3> The binder resin for a non-aqueous secondary battery electrode according to <1> or <2>, wherein the binder resin does not contain a halogen element.

The second aspect of the present invention has the following features.

&Lt; 4 > A resin composition comprising a structural unit represented by the following general formula (11)

(B) having at least one structural unit selected from the group consisting of a structural unit represented by the following general formula (12), a structural unit represented by the following general formula (13) and a structural unit derived from a compound represented by the following general formula , Binder resin for non-aqueous secondary battery electrode.

(In the formula (11), R ¹¹ and R ¹² each independently represent a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms.)

(In the general formula (12), R ¹³ is a hydrogen atom or a monovalent substituent, and R ¹⁴ is a hydrogen atom or a methyl group.)

(In the formula (13), R ¹⁵ is a divalent substituent.)

(Wherein R ³¹ and R ³² are each independently a divalent substituent, R ³³ is a monovalent substituent, and any of R ³¹ to R ³³ has a vinyl group structure, s and t are each independently 0 Or 1).

<5> The binder resin for a non-aqueous secondary battery electrode according to <4>, wherein the structural unit represented by the formula (13) is derived from at least one compound selected from the group consisting of compounds represented by the following formulas (14) to

(In the general formula (14), R ¹⁶ is a hydrogen atom or a methyl group, R ¹⁷ is a hydrogen atom or a monovalent substituent, X ¹¹ is a divalent substituent having a structural unit represented by the above formula (13), and the polyalkylene glycol repeating unit , A repeating unit of a polyester diol, and a repeating unit of a polycarbonate diol.

(Wherein R ¹⁸ and R ¹⁹ are each independently a hydrogen atom or a methyl group, X ¹² is a divalent substituent having a structural unit represented by the above formula (13), a repeating unit of a polyalkylene glycol, a polyester diol And a repeating unit of a polycarbonate diol). &Lt; RTI ID = 0.0 &gt; (I) &lt; / RTI &gt;

(In the formula (16), A ¹¹ and A ¹² each independently represent a monovalent substituent having the structural unit represented by the above formula (13).)

<6> The binder resin for a non-aqueous secondary battery electrode according to <4> or <5>, wherein the structural unit represented by the formula (12) and / or the formula (13) is derived from a monomer (b) satisfying the following conditions.

The glass transition temperature of the homopolymer of the monomer (b) ≤ the glass transition temperature of the homopolymer having the structural formula (11) as the structural unit

<7> The binder resin for a non-aqueous secondary battery electrode according to any one of <4> to <6>, wherein the structural unit represented by Chemical Formula 12 and / or Chemical Formula 13 has an acidic group or a salt thereof.

(8) The polymer (B) is a polymer having the structural unit represented by the formula (11), the structural unit represented by the formula (12) and the structural unit represented by the formula (13) , And the structural unit represented by the formula (12). The binder resin according to any one of < 4 > to < 7 >

The third aspect of the present invention has the following features.

<9> A binder resin for a non-aqueous secondary battery electrode, which contains the following component (α) and / or component (β).

(?) Component (?) having a structural unit represented by the following formula (21) and a structural unit represented by the following formula (22).

(β): A mixture of a polymer (β1) having a structural unit represented by the following formula (21) and a polymer (β2) having a structural unit represented by the following formula (22).

(In the formula (21), R ²¹ is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms.)

(In the formula (22), R ²² and R ²³ are each independently a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms.)

<10> The binder resin for a non-aqueous secondary battery electrode according to <9>, wherein at least one of the polymer (α), the polymer (β1) and the polymer (β2) has a structural unit represented by the following formula (23).

(Wherein R ²⁴ and R ²⁵ are each independently a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms)

<11> The binder resin for a non-aqueous secondary battery electrode according to <9> or <10>, which is obtained by hydrolyzing the polymer (? 2).

<12> The binder resin for a nonaqueous secondary battery electrode according to any one of <4> to <11>, wherein the flexibility of the electrode is not changed when the flexibility test is performed.

(Flexibility test)

The binder resin for the non-aqueous secondary battery electrode and water are kneaded. The active material is added and kneaded. When the electrode is a positive electrode, a conductive auxiliary agent is added and kneaded, followed by adjustment to water to a coating viscosity to obtain a slurry composition. The blending amount is 2 parts by mass of the binder resin for the non-aqueous secondary battery electrode, and 5 parts by mass of the conductive auxiliary for 100 parts by mass of the active material.

The obtained slurry composition is coated on a current collector and dried to obtain an electrode in which a mixed layer having a thickness of 20 to 200 mu m is formed on the current collector.

The obtained electrode was cut into 3 cm in width and 5 cm in length, and used as a test piece.

A mandrel having a diameter of 8 mm was placed on the collector surface of the obtained test piece and the test piece was bent in such a manner that one side of the test piece was fixed with a tape so that the current collector surface was in the inside in the humidity of 10% Observe the state to evaluate the flexibility of the electrode.

<13> A binder resin composition for a nonaqueous secondary battery electrode, which comprises the binder resin for a non-aqueous secondary battery electrode according to any one of <1> to <12>.

<14> A binder resin for a non-aqueous secondary battery electrode according to any one of <1> to <12>, or a binder resin composition for a non-aqueous secondary battery electrode described in <13>, an active material, Slurry composition for battery electrode.

<15> A current collector and a composite layer provided on the current collector,

The binder layer resin composition for a non-aqueous secondary battery electrode described in any one of < 1 > to < 12 >, or the binder resin composition for a non- electrode.

<16> A current collector and a composite layer provided on the current collector,

Wherein the additive layer is obtained by coating the current collector with the slurry composition for a non-aqueous secondary battery electrode described in < 14 >, followed by drying.

<17> A non-aqueous secondary battery comprising the electrode for a non-aqueous secondary battery according to <15> or <16>.

According to the present invention, it is possible to provide a binder resin for a water-soluble non-aqueous secondary cell electrode, a binder resin composition for a non-aqueous secondary battery electrode, a slurry composition for a non-aqueous secondary battery electrode, An electrode for a secondary battery, and a nonaqueous secondary battery.

The present invention also provides a binder resin for a water-soluble non-aqueous secondary battery electrode, a binder resin composition for a non-aqueous secondary battery electrode, a slurry composition for a non-aqueous secondary battery electrode, a non-aqueous secondary battery electrode, A secondary battery can be provided.

Hereinafter, the present invention will be described in detail.

In the present invention, the term &quot; water-soluble &quot; means that the binder resin dissolves in water. Specifically, the solubility in 100 g of water at 25 DEG C (i.e., g or more. The solubility is preferably 1 g or more.

In the present specification, the term "(meth) acryl" is a general term for acryl and methacryl, "(meth) acrylate" is a general term for acrylate and methacrylate, And metal reel.

&Quot; First Solar &quot;

«Binder resin for non-aqueous secondary battery electrode»

The binder resin for a nonaqueous secondary battery electrode (hereinafter simply referred to as binder resin) of the first aspect of the present invention is a binder resin which is used as the binder resin in a slurry composition for a binder resin, an active material, Is a binder resin for a non-aqueous secondary battery electrode.

The binder resin of the first aspect of the present invention is characterized in that when the binder resin is dissolved in the water to prepare a solution having a concentration of 5% by mass and the particle size distribution is measured by a dynamic light scattering method at 25 캜, .

I _S ? 30 (i)

(In the formula (i), I _S represents the sum of the scattering intensities observed in a particle diameter range of 1 to 100 nm.)

The concentration of 5% by mass is an average value of the binder resin concentration in the slurry composition used in the production of the electrode for the non-aqueous secondary battery. That is, the value measured by the particle size distribution measurement reflects the state of the binder resin in the slurry composition.

When a binder resin having extremely high solubility in water is used, I _S can not be measured due to insufficient strength, but if solubility is low, I _S can be measured even though it is dissolved at first. This is because the polymer molecules are folded and superposed to form a mass, and the size of the mass is considered to be detected by DLS as the particle diameter.

The value of I _{S in} the above formula (i) correlates with the tin firing of the slurry composition obtained by mixing the binder resin with the active material and water, and the higher the value of I _S of the binder resin, The thermosetting property of the composition is enhanced.

When the value of I _S is 30 or more, that is, when the absolute value of the scattering intensity of the particles having a particle diameter of 1 to 100 nm is 30 or more, when the electrode for a non-aqueous secondary battery is formed by using the slurry composition, The nonaqueous secondary battery using the electrode has sufficiently superior battery characteristics.

On the other hand, when the value of I _S is less than 30, for example, when the binder resin is completely dissolved and I _S can not be measured, or when the scattering intensity of particles exceeding 100 nm is large, the uniformity of the obtained slurry composition becomes insufficient.

I _S is preferably 40 or more, and more preferably 50 or more.

On the other hand, in Patent Document 1 in the background art, the rotation radius of the polymer is measured using a solution diluted with NMP or n-heptane by a static light scattering method, but the concentration thereof is extremely low at 0.2 to 0.8 mass% . Therefore, the rotation radius is significantly different from the particle diameter of the polymer in the slurry composition. Further, in Patent Document 2, a polymer latex is prepared by emulsion polymerization using water as a polymerization medium, and then water is replaced with NMP to form a binder composition. The minimum particle size of the primary particles is measured before the NMP replacement, that is, in the latex state, and the particle lapse of the polymer in the slurry composition is greatly different.

The &quot; latex &quot; and &quot; solution &quot; can be distinguished by whether or not the particle diameter is observed by measurement of the particle diameter distribution of the laser diffraction type. In the case of &quot; solution &quot;, the particle diameter is not observed by the laser diffraction particle size distribution measurement.

The value of I _S can be controlled by solubility of the polymer (A) contained in the binder resin, constituent unit composition, mass average molecular weight, stereoregularity, crosslinking density and the like.

For example, when a certain polymer is used, when the scattering intensity of particles exceeding 100 nm is large and I _S is less than 30, if a polymer having higher solubility in water than the polymer is blended, I _S becomes larger.

In addition, when the binder resin is completely dissolved and I _S can not be measured, the larger the mass average molecular weight, the lower the solubility in water and the larger the I _S.

The binder resin of the first aspect of the invention, the active material of 100 parts by mass of the conductive additive and 5 parts by mass of the art binder resin 2 parts by mass, a mixture of 40 mass parts of water, and a slurry composition, a shear rate of 0.03sec ^-1 100sec from after varying ^-1 to measure the viscoelasticity, when the shear rate by a program while changing the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, a viscoelasticity measuring line at 25 ℃, the following formula (ii) Is satisfied.

? _0.1 /? ₈₀ ? 20 (ii)

(Formula (ii) of, η _{0 .1} indicates the viscosity at the shear rate 0.1sec ^-1 when varying the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, η is the shear rate of ₈₀ varying from 100sec ^-1 to 0.03sec ^-1 represents the viscosity of the shear speed at 80sec ^-1 when measuring the viscoelasticity.)

The active material used in the preparation of the slurry composition is made of lithium cobalt oxide (LCO) in the case of an anode electrode (hereinafter, simply referred to as an anode) and graphite in the case of a cathode electrode (hereinafter simply referred to as a cathode). The conductive additive is acetylene black.

The viscoelasticity measurement of the slurry composition may be carried out using either a rheometer of a stress control system or a strain control system, but a rheometer of a stress control system is preferable in view of the viscosity (slurry viscosity) of the slurry composition. Conditions such as the plate used for the measurement are not particularly limited, but it is preferable to use a cone plate of? 40 mm and angle of 2 degrees and setting the gap to 69 mm in view of being able to cope with a wide slurry viscosity range. The measurement temperature is 25 캜.

Shear rate program, first of all, while varying a shear rate of 100sec ^-1 to from 0.03sec ^-1 measure the viscoelasticity of the slurry composition. Then, while changing the shear rate of 0.03sec ^-1 to from 100sec ^-1 and again measuring the viscoelasticity of the slurry composition.

The higher the value of η _{0 .1} / η _80, indicates that high thixotropic slurry composition. If η _{0 .1} / η value of ₈₀ is more than 20, a thixotropic slurry of the composition can be said to be satisfactory.

If η _{0 .1} / η is less than the value of ₈₀ is 20, the active material and conductive additive are precipitated with time (經時) are present, the material mixture layer becomes non-uniform.

η upper limit value of _{0 .1} / η ₈₀ is not particularly limited, but is in view of preventing the solidification of the rapid slurry composition after coating the slurry composition, less than 500 are preferred.

η value of _{0 .1} / η _80, can be adjusted by a solubility in the water, the constituent unit composition, the weight average molecular weight, stereoregularity and the crosslinking density of the polymer (A) contained in the binder resin.

For example, in the case of a slurry composition using a polymer which, η _{0 .1} / 20 is less than when the value of η _80, than when the polymer solubility in the water blended with low polymer, the greater the η _0.1 / η _80.

Further, in the case of a slurry composition using a polymer which, η _{0 .1} / ₈₀ When the value of η is larger than 500, the weight average molecular weight or viscosity average molecular weight if the formulation a small polymer, increase the solubility in the water, η _0.1 /? ₈₀ tends to be smaller.

(Polymer (A))

The polymer (A) is a polymer contained in the binder resin of the first aspect of the present invention, and imparts appropriate viscosity to the slurry composition to impart stability and battery characteristics of the slurry composition.

In the first aspect of the present invention, since the particle size distribution measurement by DLS is performed using the binder resin as the concentration of 5 mass%, the binder resin is dissolved in the water used for preparing the slurry composition for the nonaqueous secondary battery electrode It is necessary to have water solubility which can be a solution of 5% by mass or more in concentration. Therefore, the polymer (A) itself constituting the binder resin also has a water-solubility that can be dissolved in water used for preparing a slurry composition for a non-aqueous secondary battery electrode to a concentration of 5% by mass or more.

The polymer (A) can be obtained by polymerizing a polymer (A) which is chemically synthesized using a low-molecular compound as a raw material, with the exception of natural polymers such as xanthan gum, mannan and salts thereof, and natural polymers such as carboxymethylcellulose (CMC), methyl cellulose, hydroxymethyl cellulose, (Hereinafter, referred to as a synthetic polymer), and is not particularly limited. Synthetic polymers are preferred because they do not use natural or natural materials as raw materials, and the quality of each lot is relatively stable.

The polymer (A) may have a structural unit derived from a monomer containing an acidic group and / or a salt thereof (hereinafter referred to as monomer (a1)). Examples of the acidic group include a carboxy group, a sulfonic acid group, and a phosphoric acid group. Examples of the salt of the acid group include an alkali metal salt, an alkaline earth metal salt, an ammonium salt, and a substituted ammonium salt of an acid group.

 Examples of the alkali metal include lithium, sodium, potassium and the like.

 Examples of the alkaline earth metals include magnesium and calcium.

 As the substituted ammonium, for example, knowledge (fat type) ammonium compounds, cyclic saturated ammonium compounds, and cyclic unsaturated ammonium compounds can be given.

Examples of the monomer (a1) include carboxyl group-containing monovinyl monomers and salts thereof such as (meth) acrylic acid, (anhydrous) itaconic acid, fumaric acid, crotonic acid and (anhydrous) maleic acid; Monovinyl monomers containing sulfonic acid groups such as (meth) allylsulfonic acid, (meth) allyloxybenzenesulfonic acid, and styrene sulfonic acid, and salts thereof; (Meth) acryloyloxyethyl phosphate, 2- (meth) acryloyloxyethyl acid phosphate, monoethanolamine, diphenyl ((meth) acryloyloxyethyl) phosphate, (Meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, acid phosphoxylpolyoxypropylene glycol (meth) acrylate, ) Acrylate, and salts thereof, and the like.

The polymer (A) may have a constitutional unit derived from a monomer containing a hydroxyl group, an ether bond or an amino group (hereinafter referred to as monomer (a2)) except for the monomer (a1).

Examples of the monomer (a2) include (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-3-hydroxypropyl, (meth) Hydroxy group-containing monovinyl monomers such as hydroxy-n-butyl; (Meth) acrylic acid esters such as (meth) acrylic acid-2-ethoxyethyl, (meth) acrylate-1-ethoxyethyl, (meth) acrylate butoxyethyleneglycol, Ether bond-containing monovinyl monomer; (Meth) acrylamide, 2-dimethylaminoethyl (meth) acrylate, N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, and amino group-containing monovinyl monomers such as? -caprolactam and N-vinylcarbazole.

On the other hand, the "vinyl monomer" is a vinyl group or a compound having at least one? -Methyl vinyl group in which a hydrogen atom bonded to a carbon atom at? -Position of a vinyl group is substituted with a methyl group.

These monomers (a1) and (a2) may be used singly or in combination of two or more.

The total content of the monomer (a1) unit and the monomer (a2) unit in the polymer (A) is not particularly limited as long as the polymer (A) dissolves in water. The total amount of all the constituent units constituting the polymer (A) %) Is preferably 20 mol% or more, more preferably 30 mol% or more, and particularly preferably 40 mol% or more. When the polymer (A) contains the monomer (a1) unit and the monomer (a2) unit in a total content of 40 mol% or more (homopolymer or copolymer), the solubility in water is particularly improved, Adhesion (adhesion), and the like can be formed.

The upper limit of the total content of the monomer (a1) unit and the monomer (a2) unit is not particularly limited, and may be 100 mol%.

The content ratio of each of the monomer (a1) unit and the monomer (a2) unit is not particularly limited and may be appropriately set in a range of 0 to 100 mol%. When the polymer (A) contains a unit other than the monomer (a1) unit and the monomer (a2) unit (arbitrary unit), it can be suitably set in consideration of balance with arbitrary units.

Examples of the arbitrary unit include monofunctional monomers having one polymerizable functional group other than the monomer (a1) and the monomer (a2) (for example, a vinyl group, an a-methylvinyl group, an allyl group, a3)), and a unit derived from at least two polyfunctional monomers (hereinafter referred to as monomer (a4)). Particularly, when the monomer (a4) is used, the polymer (A) has a crosslinked structure, and mechanical properties and the like are improved.

Examples of the monomer (a3) include (meth) acrylates such as methyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and hexyl (meth) acrylate; Vinyl ketones such as methyl vinyl ketone and isopropyl methyl ketone; Cyanated vinyl monomers such as acrylonitrile, methacrylonitrile,? -Cyanoacrylate, dicyanobonylidene, and fumaronitrile ethyl; Halogenated vinyl monomers such as vinyl chloride, vinyl bromide, and vinylidene chloride; Aromatic vinyl monomers such as styrene and? -Methylstyrene; Maleimides such as maleimide and phenylmaleimide; Vinyl acetate, and the like.

These monomers (a3) may be used singly or in combination of two or more.

The content of the monomer (a3) unit in the polymer (A) is preferably 0 to 10 mol%, more preferably 0.01 to 5 mol%, in the total (100 mol%) of all the constituent units constituting the polymer (A) Do.

Examples of the monomer (a4) include ethylene glycol di (meth) acrylate and triethylene glycol di (meth) acrylate.

These monomers (a4) may be used singly or in combination of two or more kinds.

The content of the monomer (a4) unit in the polymer (A) is preferably 0 to 10 mol%, more preferably 0.01 to 5 mol%, in the total (100 mol%) of all the constituent units constituting the polymer (A) Do.

The polymer (A) can be prepared by polymerizing the monomer (a1) or the monomer (a2) singly or by copolymerizing the monomer (a1) and / or the monomer (a2) with any monomer (monomer (a3) a4) or the like). The polymerization method thereof is not particularly limited and is selected from solution polymerization, suspension polymerization, emulsion polymerization and the like depending on the type of the monomer and the solubility of the resulting polymer.

For example, in the case where each monomer is soluble in water and the affinity of the resulting polymer to water is high, aqueous solution polymerization can be selected. The aqueous solution polymerization is a method in which a monomer and a water-soluble polymerization initiator are dissolved in water to obtain a polymer by heat from outside or polymerization heat.

When the solubility of each monomer in water is small, suspension polymerization, emulsion polymerization, and the like can be selected. The emulsion polymerization is a method in which a monomer, an emulsifier, a water-soluble polymerization initiator or the like is added to water and heated under stirring to obtain a polymer.

The initiator used in the polymerization is not particularly limited, but an optional initiator can be used from a thermal polymerization initiator, a photopolymerization initiator and the like according to a polymerization method. Specific examples thereof include azo compounds and peroxides.

In addition, a chain transfer agent may be present in the polymerization system.

The polymerization temperature and time are not particularly limited, but from the viewpoint of the progress of the polymerization reaction, the stability of the compound and the operability, it is preferably 0 to 200 ° C for 0.1 to 100 hours.

In addition, by removing the water by filtration, centrifugal separation, heat drying, vacuum drying and a combination thereof, a powdery polymer (A) is obtained.

The molecular weight of the polymer (A) is not particularly limited, but the viscosity average molecular weight (Mv) is preferably 10,000 to 2,000,000, more preferably 100,000 to 1,500,000, and particularly preferably 500,000 to 1,000,000. If the lower limit is above the lower limit, the binding property is higher. If the lower limit is below the upper limit, the water-solubility becomes higher and the dispersibility of the conductive auxiliary becomes better.

 The viscosity average molecular weight (Mv) is calculated from the viscosity of the aqueous solution of the polymer (A) as a viscosity-converted molecular weight using poly N-vinylformamide (hereinafter referred to as PNVF) as a standard material. An example of a method of calculating the viscosity average molecular weight is shown below.

Calculation method of viscosity average molecular weight:

Calculates an aqueous solution of the reduced viscosity (ηsp / C) and a Huggins equation, from the intrinsic viscosity (ηsp / C = [η] + K '[η] 2 C) [η] of the polymer (A). In the above formula, "C" is the concentration (g / dL) of the polymer (A) in the aqueous solution of the polymer (A). The method for measuring the reduced viscosity of the aqueous solution of the polymer (A) is described below.

The viscosity average molecular weight (&quot; M &quot; in the formula) is calculated from the intrinsic viscosity [] obtained and the formula of Mark-Houwink ([eta] = KMa).

On the other hand, in the 1N saline solution, the parameters of PNVF are K = 8.31 x 10 ^-5 , a = 0.76, and K '= 0.31.

Method of measuring reduced viscosity:

First, the polymer (A) is dissolved in 1N brine so that the concentration of the polymer (A) becomes 0.1% by mass to obtain an aqueous solution of the polymer (A). The aqueous solution of the obtained polymer (A) is subjected to measurement of a flow time (t ₁ ) at 25 캜 using an Ostwald viscometer.

Separately, as a blank, the dropping time (t ₀ ) at 25 ° C was measured for 1N saline using an Oswald viscometer.

From the obtained dropping time, the reduced viscosity is calculated by the following formula (iii).

_{ηsp / C = {(t 1} / t 0) -1} / C ··· (iii)

(In the formula (iii), C is the concentration (g / dL) of the polymer (A) in the aqueous solution of the polymer (A)

The polymer (A) contained in the binder resin of the first embodiment of the present invention may be one kind or two or more kinds.

Further, it is preferable that the binder resin of the first aspect of the present invention does not contain a halogen element. In the case where the binder resin contains a halogen element, the non-aqueous secondary battery provided with the electrode produced by using the binder resin can be produced by an electrochemical reaction between the electrolyte and the binder resin during charging and discharging, Hydrogen is generated, and corrosion of active materials and the like is concerned.

 If the binder resin does not contain a halogen element, the generation of hydrogen halide at the time of charging and discharging is suppressed, so that the active material is hardly corroded.

Here, "not containing a halogen element" means that a polymer containing a halogen element (for example, a fluorine-containing polymer such as PVDF, polytetrafluoroethylene, polypentafluoropropylene, etc.) &Lt; / RTI &gt;

Examples of the form of the binder resin include a powder phase, a doped phase dissolved or dispersed in a solvent such as water, and the like. From the viewpoints of stability during storage and distribution, economic efficiency, and easiness of handling, powdery form is preferable for storage and distribution.

As described above, the binder resin of the first aspect of the present invention satisfies the above formula (i), so that a slurry composition having a good tin-firing property can be obtained, and further, the binder resin can be flowed in powder form. The better the tic baking of the slurry composition, the better the storage stability of the slurry composition, the uniformity of the mix layer, the better the adhesion (tackiness), and the better the battery characteristics.

«Binder resin composition for non-aqueous secondary battery electrode»

The binder resin composition for a nonaqueous secondary battery electrode of the first aspect of the present invention (hereinafter simply referred to as a binder resin composition) contains the binder resin of the first aspect of the present invention described above.

Examples of the form of the binder resin composition include a powder phase, a doped phase dissolved or dispersed in a solvent such as water, and the like. From the viewpoints of stability during storage and distribution, economic efficiency, and easiness of handling, powdery form is preferable for storage and distribution.

The content of the binder resin in the powdery binder resin composition is preferably 50% by mass or more, more preferably 80% by mass or more, and may be 100% by mass. If the lower limit value is not less than the lower limit, the effect of the present invention is remarkably exhibited.

The binder resin composition of the first aspect of the present invention may contain a binder resin (other binder resin) other than the binder resin of the first aspect of the present invention, a viscosity adjusting agent, a binding property An additive such as an improving agent, a dispersing agent and the like may be contained.

Examples of other binder resins include vinyl acetate copolymer, styrene-butadiene block copolymer (SBR), acrylic acid modified SBR resin (SBR type latex), and acrylic rubber latex.

The viscosity adjusting agent improves the coating property of the binder resin. Examples of the viscosity adjuster include cellulose polymers such as carboxymethyl cellulose, methyl cellulose and hydroxypropyl cellulose, and ammonium salts thereof; Poly (meth) acrylates such as poly (meth) acrylate; Polyvinyl alcohol, polyethylene oxide, polyvinyl pyrrolidone, a copolymer of acrylic acid or an acrylate and a vinyl alcohol, a copolymer of maleic anhydride or maleic acid or fumaric acid and a vinyl alcohol, a modified polyvinyl alcohol, a modified polyacrylic acid, polyethylene glycol , And polycarboxylic acids.

The additive such as the viscosity adjusting agent finally remains on the electrode. Therefore, it is preferable that the additive is not added as much as possible. However, when added, it is preferable to use an additive having electrochemical stability.

When the binder resin composition contains an additive such as a viscosity adjusting agent, the content thereof is preferably 50% by mass or less when the binder resin composition is 100% by mass. However, the content of the additive is preferably as small as possible from the viewpoint of further improving battery performance.

The binder resin composition of the first aspect of the present invention is a binder resin composition obtained by dissolving the binder resin composition in water to prepare a solution having a concentration of 5% by mass and measuring particle size distribution by dynamic light scattering method at 25 캜, ).

I _S ? 30 (i)

(In the formula (i), I _S represents the sum of the scattering intensities observed in a particle diameter range of 1 to 100 nm.)

The binder resin composition of the first aspect of the present invention is obtained by mixing 100 parts by mass of the active material, 5 parts by mass of the conductive auxiliary agent, 2 parts by mass of the binder resin composition and 40 parts by mass of water to prepare a slurry composition, to then varying from ^-1 to 100sec ^-1 measuring viscoelasticity, when the shear rate by a program while changing the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, a viscoelasticity measuring line at 25 ℃, It is preferable to satisfy the formula (ii).

? _0.1 /? ₈₀ ? 20 (ii)

(Formula (ii) of, η _{0 .1} indicates the viscosity at the shear rate 0.1sec ^-1 when varying the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, η is the shear rate of ₈₀ varying from 100sec ^-1 to 0.03sec ^-1 represents the viscosity of the shear speed at 80sec ^-1 when measuring the viscoelasticity.)

The binder resin composition can be produced by a known method. For example, the binder resin of the first aspect of the present invention in the form of a powder and, if necessary, a powdery additive may be mixed in powder form, or the binder resin of the first aspect of the present invention in powder form and the powdery additive may be dispersed in water .

Since the binder resin composition of the first embodiment of the present invention described above contains the binder resin of the first aspect of the present invention described above, it is possible to obtain a slurry composition having good tic-firing and to distribute it in powder form. The better the tic baking of the slurry composition, the better the storage stability of the slurry composition, the uniformity of the mix layer, the better the adhesion (tackiness), and the better the battery characteristics.

&Quot; Slurry composition for non-aqueous secondary battery electrode &

The slurry composition for a nonaqueous secondary battery electrode according to the first aspect of the present invention (hereinafter, simply referred to as a slurry composition) is obtained by mixing the binder resin of the first aspect of the present invention or the binder resin composition of the first aspect of the present invention , An active material, and water. That is, the slurry composition of the first aspect of the present invention is a slurry composition containing a binder resin, an active material and water, wherein the binder resin is dissolved in the water to prepare a solution having a concentration of 5 mass% Is a slurry composition for a nonaqueous secondary battery electrode satisfying the following formula (i) when particle size distribution measurement is performed by a light scattering method.

I _S ? 30 (i)

(In the formula (i), I _S represents the sum of the scattering intensities observed in a particle diameter range of 1 to 100 nm.)

The slurry composition of the first aspect of the present invention preferably further contains a conductive auxiliary agent and is obtained by mixing 100 parts by mass of the active material, 5 parts by mass of the conductive auxiliary agent, 2 parts by mass of the binder resin and 40 parts by mass of water, to, and then, while changing the shear rate up to 100sec ^-1 from 0.03sec ^-1 measuring the viscoelasticity by the shear rate to program while changing the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity at 25 ℃ When the viscoelasticity measurement is performed, it is preferable that the following formula (ii) is satisfied.

? _0.1 /? ₈₀ ? 20 (ii)

(Formula (ii) of, η _{0 .1} indicates the viscosity at the shear rate 0.1sec ^-1 when varying the shear rate of 0.03sec ^-1 to from 100sec ^-1 measuring viscoelasticity, η is the shear rate of ₈₀ varying from 100sec ^-1 to 0.03sec ^-1 represents the viscosity of the shear speed at 80sec ^-1 when measuring the viscoelasticity.)

The binder resin used in the slurry composition of the first aspect of the present invention is the binder resin of the first aspect of the present invention described above, and a detailed description thereof will be omitted. Further, the binder resin composition used in the slurry composition of the first aspect of the present invention is the binder resin composition of the first aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the slurry composition of the first aspect of the present invention is not particularly limited, but it is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass in the total solid content of the slurry composition (total components excluding the solvent) More preferable. If it is 0.01% by mass or more, the adhesiveness (tackiness) between the mixture layer and the current collector formed using the slurry composition becomes higher. When the amount is 15% by mass or less, the active material and optional components to be described later (for example, a conductive auxiliary agent) can be sufficiently contained.

The active material used in the slurry composition of the first aspect of the present invention is not particularly limited, and any known electrode may be used depending on the application for an electrode to be produced using the slurry composition.

For example, in the case of a lithium ion secondary battery, the active material (positive electrode active material) of the positive electrode has a higher potential (relative to metallic lithium) than the active material (negative electrode active material) of the negative electrode and is capable of absorbing and desorbing lithium ions Material is used.

Specific examples of the positive electrode active material include lithium-containing metal complex oxides containing lithium, at least one metal selected from iron, cobalt, nickel, manganese and vanadium, polyaniline, polythiophene, polyacetylene and derivatives thereof, poly Polyaniline and derivatives thereof such as polyphenylene and derivatives thereof, polypyrrole and derivatives thereof, polythienylene and derivatives thereof, polypyridine diisocyanate and derivatives thereof, polyisocyanatophenylene and derivatives thereof, and the like. Polymer. As the conductive polymer, a polymer of an aniline derivative soluble in an organic solvent is preferable. These cathode active materials may be used singly or in combination of two or more kinds.

Examples of the negative electrode active material include carbon materials such as graphite, amorphous carbon, carbon fiber, coke and activated carbon; A composite of the carbon material and a metal such as silicon, tin, silver, or an oxide thereof, and the like. These negative electrode active materials may be used singly or in combination of two or more kinds.

In the lithium ion secondary battery, it is preferable to use a lithium-containing metal complex oxide as the positive electrode active material and graphite as the negative electrode active material. With such a combination, the voltage of the lithium ion secondary battery can be increased to 4V or more, for example.

The content of the active material in the slurry composition of the first aspect of the present invention is not particularly limited, but it is preferably 80 to 99.9 mass%, more preferably 85 to 99 mass% of the total solid content of the slurry composition (total components excluding the solvent) desirable. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. When it is 99.9 mass% or less, adhesion between the mixture layer and the current collector is good.

As the solvent contained in the slurry composition of the first aspect of the present invention, at least water is used, but a mixed solvent of water and an organic solvent may be used. As the organic solvent, a binder resin is selected which can be dissolved or dispersed uniformly. For example, NMP, an ester solvent (ethyl acetate, n-butyl acetate, butyl cellosolve acetate, butyl carbitol acetate, etc.) (Acetone, methyl ethyl ketone, methyl isobutyl ketone and the like), and the like can be given as examples of the solvent used in the present invention. Examples of the solvent include methyl ethyl ketone, diglyme, triglyme and tetraglyme. These organic solvents may be used alone or in combination of two or more.

Examples of the mixed solvent include a mixed solvent of water and an alcohol-based solvent, a mixed solvent of water and an NMP and an ester-based solvent, and a mixed solvent of water and an NMP and a grit-based solvent.

However, since the organic solvent has a high environmental load, it is preferable to use water alone as the solvent.

The content of the solvent in the slurry composition of the first aspect of the present invention may be the minimum amount necessary to maintain the state in which the binder resin is dissolved at room temperature, but is preferably from 5 to 50 mass%, more preferably from 10 to 40 mass% Do. The content of the solvent in the slurry composition is determined in consideration of the viscosity which is easily applied to the current collector when the slurry composition is formed using the slurry composition.

The slurry composition of the first aspect of the present invention may contain components (optional components) other than the binder resin, the active material and the solvent, if necessary.

Examples of optional components include conductive additives, antioxidants, thickeners, and the like.

Particularly, in the case where the slurry composition of the first aspect of the present invention forms the mixture layer of the positive electrode, or when the mixture layer of the negative electrode containing fine metal particles such as silicon is formed, it is preferable that the slurry composition contains a conductive additive . By containing the conductive auxiliary agent, electrical contact between the active materials and between the active material and the metal fine particles can be improved, and battery performance such as discharge rate characteristics of the nonaqueous secondary battery can be further improved.

Examples of the conductive agent include acetylene black, carbon black, graphite, channel black, fullerene, carbon nanotube, and graphene. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the slurry composition of the first aspect of the present invention is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.1 to 7% by mass in the total solid content (excluding the solvent) More preferable. If it is 0.01% by mass or more, the battery performance is higher. When it is 10 mass% or less, adhesion between the mixture layer and the current collector is good.

The slurry composition of the first aspect of the present invention can be produced by kneading a binder resin, an active material, a solvent, and optional components (such as a conductive auxiliary agent) as required. The kneading can be carried out by a known method.

In the preparation of the slurry, the binder resin of the first embodiment of the present invention may be used in the form of a powder, or may be dissolved in a solvent in advance before being mixed with an active material or an optional component (for example, a conductive auxiliary agent) to be used as a resin solution.

The above-described slurry composition of the first aspect of the present invention contains the binder resin of the first aspect of the present invention or the binder resin composition of the first aspect of the present invention, and therefore, the tincture is good. As a result, the storage stability of the slurry composition, the uniformity of the mixed layer, and the adhesiveness (cohesiveness) are improved and the battery characteristics are improved.

«Electrodes for non-aqueous secondary batteries»

An electrode for a secondary battery according to the first aspect of the present invention (hereinafter simply referred to as an electrode) comprises a current collector and a mixture layer provided on the current collector, A binder resin, and an active material.

The current collector may be a conductive material, and examples thereof include metals such as aluminum, copper, and nickel.

The shape of the current collector can be determined according to the shape of the target battery, and examples thereof include a thin film, a mesh, and a fibrous. Among them, a thin film is preferable.

The thickness of the current collector is not particularly limited, but is preferably 5 to 30 m, more preferably 8 to 25 m.

The binder resin used in the compounding layer is the binder resin of the first aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the mixed layer is not particularly limited, but is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass. If it is 0.01% by mass or more, the adhesiveness (binding property) between the mixture layer formed by using the slurry composition of the first aspect of the present invention and the collector becomes higher. When the content is 15 mass% or less, the active material and optional components (for example, conductive additives) can be sufficiently contained, thereby improving battery characteristics.

As the active material to be used in the mixed layer, the same materials as the above-mentioned active materials in the description of the slurry composition of the first aspect of the present invention can be mentioned.

The content of the active material in the mixed layer is not particularly limited, but is preferably 80 to 99.9 mass%, and more preferably 85 to 99 mass%. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. If it is 99.9 mass% or less, the adhesion (adhesion) between the mixture layer and the current collector is good.

In the case where the electrode of the first aspect of the present invention is an anode or an anode containing metal fine particles such as silicon, the compound layer preferably contains a conductive auxiliary agent. By containing a conductive auxiliary agent, battery performance can be further improved.

As the conductive auxiliary agent, there may be mentioned the same ones as the conductive auxiliary agents exemplified above in the explanation of the slurry composition of the first aspect of the present invention described above. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the mixed layer is not particularly limited, but is preferably 0.01 to 10% by mass, and more preferably 0.1 to 7% by mass. If it is 0.01% by mass or more, the battery performance is higher. If it is 10% by mass or less, the adhesiveness (binding property) between the mixture layer and the current collector is good.

The composite layer can be formed by coating the current collector with the slurry composition of the first aspect of the present invention described above and drying it.

When the current collector is in the form of a thin film or a network, the mixture layer may be provided on one side or both sides of the current collector.

The coating method of the slurry composition is not particularly limited as long as the slurry composition can be applied to the current collector in an arbitrary thickness. For example, a doctor blade method, a dipping method, a reverse roll method, a direct roll method, a gravure method, And the like.

The coating amount can be appropriately set in accordance with the thickness of the mixture layer to be formed.

The applied slurry composition is dried to remove the solvent to form a mixed layer.

The drying method is not particularly limited as long as the solvent can be removed. For example, when the slurry composition contains water as a solvent, a method of heating the slurry composition to above the boiling point of water; When the slurry composition contains a mixed solvent of water and an organic solvent as a solvent, a method of heating the mixture at a temperature higher than the boiling point of water and an organic solvent; A method of blowing hot air, hot air or low-humidity air; A method of evaporating the solvent under reduced pressure conditions; (Circle) method of irradiating infrared rays or electron beams.

After drying, the formed mixture layer may be rolled if necessary. By rolling, the area of the mixture layer can be widened and the thickness can be adjusted to an arbitrary thickness.

Examples of the rolling method include a method such as a die press or a roll press.

On the other hand, the obtained electrode may be cut to an arbitrary dimension.

The thickness of the compounded layer can be appropriately determined depending on the kind of the active material, but is preferably 20 to 200 m, more preferably 30 to 120 m.

The electrode of the first aspect of the present invention can be used for both the positive electrode and the negative electrode of the non-aqueous secondary battery. Particularly, it is suitable as an electrode for a lithium ion secondary battery.

In the electrode of the first aspect of the present invention described above, since the mixture layer containing the binder resin of the first aspect of the present invention or the binder resin composition of the first aspect of the present invention is formed on the current collector, The adhesion to the current collector (binding property) is high, and the battery characteristics are improved.

«Non-aqueous secondary battery»

The non-aqueous secondary battery of the first aspect of the present invention (hereinafter, simply referred to as a battery) comprises the non-aqueous secondary battery electrode of the first aspect of the present invention described above.

The &quot; nonaqueous secondary battery &quot; is a nonaqueous electrolyte which does not contain water as an electrolyte and includes, for example, a lithium ion secondary battery. The nonaqueous secondary battery generally includes electrodes (positive electrode and negative electrode), a nonaqueous electrolyte, and a separator. For example, a non-aqueous secondary battery in which a positive electrode and a negative electrode are disposed with a separator (for example, a porous film made of polyethylene or polypropylene) permeable therethrough and a nonaqueous electrolyte impregnated therebetween; A winding body obtained by winding a laminate composed of a positive electrode / separator having a negative electrode / separator / positive collector layer on both sides of the current collector formed on both sides thereof with rollers (and wound) And a cylindrical non-aqueous secondary battery accommodated in a can (a metal casing of a user's bottom).

As the non-aqueous electrolyte, an electrolytic solution obtained by dissolving a solid electrolyte in an organic solvent can be mentioned.

Examples of the organic solvent for the electrolytic solution include carbonates such as propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate; lactones such as? -butyrolactone; Ethers such as trimethoxymethane, 1,2-dimethoxyethane, diethyl ether, 2-ethoxyethane, tetrahydrofuran and 2-methyltetrahydrofuran; Sulfoxides such as dimethyl sulfoxide; Oxoselenes such as 1,3-dioxolane and 4-methyl-1,3-dioxolane; Nitrogenous compounds such as acetonitrile, nitromethane and NMP; Esters such as methyl formate, methyl acetate, butyl acetate, methyl propionate, ethyl propionate and phosphoric acid triester; Glymes such as diglyme, triglyme and tetraglyme; Ketones such as acetone, diethyl ketone, methyl ethyl ketone, and methyl isobutyl ketone; Sulfolanes such as sulfolane; Oxazolidinones such as 3-methyl-2-oxazolidinone; 1,3-propane sultone, 4-butaine sultone, naphtha sultone, and the like. These organic solvents may be used alone or in combination of two or more.

The solid electrolyte can be a known one depending on the kind of the non-aqueous secondary battery or the active material. For example, in the case of a lithium ion secondary battery, any known lithium salt may be used, and LiClO ₄ , LiBF ₄ , LiI, LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , LiAsF ₆ , LiSbF ₆ , LiAlCl ₄ , LiCl , LiBr (C ₂ H ₅ ) ₄ , LiCH ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N and Li [(CO ₂ ) ₂ ] ₂ B.

As the electrolyte of the lithium ion secondary battery, it is preferable that LiPF ₆ is dissolved in a carbonate.

In the battery of the first aspect of the present invention, the electrode of the first aspect of the present invention is used for either or both of the positive electrode and the negative electrode.

When either the positive electrode or the negative electrode is the electrode of the first aspect of the present invention, a known electrode may be used as the other electrode.

As the separator, known ones can be used. A porous polymer film prepared from a polyolefin-based polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, and an ethylene / methacrylate copolymer, They can be laminated. In addition, nonwoven fabrics made of conventional porous nonwoven fabrics such as high melting point glass fibers, polyethylene terephthalate fibers, and the like can be used, but the present invention is not limited thereto.

The method of manufacturing the battery of the first aspect of the present invention is not particularly limited, and a known method may be employed. An example of a method of manufacturing a lithium ion secondary battery will be described below.

First, the positive electrode and the negative electrode are disposed to face each other with a separator interposed therebetween, and the battery is inserted into the battery container according to the shape of the battery, and wound or hooped, Weld to the bottom.

Next, the non-aqueous electrolyte is injected into the battery container, the tap terminal welded to the collector of the positive electrode is welded to the cap of the battery in advance, the cap is disposed on the top of the battery container with the insulating gasket interposed therebetween, The portion where the battery can is contacted is tightened to seal it to form a lithium ion secondary battery.

The shape of the battery may be a coin shape, a cylindrical shape, a square shape, or a flat shape.

The battery according to the first aspect of the present invention described above has the electrode of the first aspect of the present invention and therefore has excellent battery characteristics.

The "second sun"

«Binder resin for non-aqueous secondary battery electrode»

The binder resin for a nonaqueous secondary battery electrode of the second aspect of the present invention (hereinafter simply referred to as binder resin) is a binder resin comprising a structural unit represented by the following general formula (11), a structural unit represented by the following general formula (12) (B) having at least one structural unit selected from the group consisting of a structural unit derived from a structural unit derived from a compound represented by the following general formula (31), and a structural unit derived from a compound represented by the following general formula (31).

(11)

[Chemical Formula 12]

[Chemical Formula 13]

(31)

In the formula (11), R ¹¹ and R ¹² each independently represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms.

Specific examples of the hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl and pentyl groups. The hydrocarbon group may also be a linear chain substituent.

From the viewpoint of enhancing the water-solubility of the resulting polymer (B), when R ¹¹ and R ¹² are hydrocarbon groups, the number of carbon atoms is preferably small. R ¹¹ and R ¹² are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms , A hydrogen atom or a methyl group is more preferable. Particularly, from the viewpoint of improving the water solubility, it is preferable that R ¹¹ is a hydrogen atom and R ¹² is a hydrogen atom or a methyl group, and it is particularly preferable that R ¹² is a hydrogen atom.

When the total amount of the constituent units constituting the polymer (B) is 100 mol%, the content of the structural unit represented by the above formula (11) is preferably from 1 to 99.9 mol%, more preferably from 10 to 99 mol% And particularly preferably from 20 to 99 mol%. When the content of the structural unit represented by the above-mentioned formula (11) is within the above range, it is difficult to swell the electrolyte solution (non-aqueous electrolyte) when used in an electrode as described later in detail, .

Examples of the monomer (hereinafter referred to as "monomer (b1)") originating from the structural unit represented by the formula (11) include N-vinylformamide and N-vinyl acetamide.

In the general formula (12), R ¹³ is a hydrogen atom or a monovalent substituent, and R ¹⁴ is a hydrogen atom or a methyl group.

Examples of the monovalent substituent include hydrocarbon groups and various substituents including hetero atoms such as oxygen, sulfur and nitrogen atoms.

Specific examples of R ¹³ include a basic group and its salt such as a hydrogen atom, a hydroxyl group, a thiol group and an amino group, an alkyl group having 1 to 10 carbon atoms, and an alkoxy group having an alkyl group having 1 to 10 carbon atoms. But is not limited thereto. When an acid is formed by bonding with the carbonyl group of the structural unit represented by the above formula (12), a salt thereof may be formed. In the structure of R ¹³ , an acidic group such as a hydroxyl group, a thiol group, a phosphoric acid group, a sulfonic acid group or a carboxy group, a salt thereof, or a basic group such as an amino group or a salt thereof may be contained.

When the total amount of the constituent units constituting the polymer (B) is 100 mol%, the content of the structural unit represented by the formula (12) is preferably 0.1 to 90 mol%, more preferably 1 to 80 mol%. When the content of the structural unit represented by the formula (22) is 0.1 mol% or more, an electrode having excellent flexibility can be formed.

Examples of the monomer (hereinafter referred to as "monomer (b2)") derived from the structural unit represented by Formula (12) include methyl (meth) acrylate, propyl (meth) acrylate, butyl (Meth) acrylates such as hexyl (meth) acrylate and 2-methoxyethyl acrylate; (Meth) acrylic acid and its salts; Monovinyl monomers containing sulfonic acid groups such as (meth) allylsulfonic acid, (meth) allyloxybenzenesulfonic acid, and styrene sulfonic acid, and salts thereof; (Meth) acryloyloxyethyl phosphate, 2- (meth) acryloyloxyethyl acid phosphate, monoethanolamine, diphenyl ((meth) acryloyloxyethyl) phosphate, (Meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, acid phosphoxylpolyoxypropylene glycol (meth) acrylate, ) Acrylate, and salts thereof; Vinyl ketones such as (meth) acrylamide, methyl vinyl ketone, and isopropyl methyl ketone; (Meth) acrylamide, and the like, but are not limited thereto.

These monomers (b2) may be used singly or in combination of two or more.

In the above formula (13), R ¹⁵ is a divalent substituent.

Examples of the divalent substituent include a linear or branched divalent hydrocarbon group or a divalent substituent obtained by removing two hydrogen atoms from any carbon atom of an aromatic ring or alicyclic ring, and they may be single or may be bonded to another substituent, The skeleton or substituent may contain a hetero atom.

Specifically, there may be mentioned straight or branched divalent hydrocarbon groups such as ethylene, propylene and butylene groups, aromatic rings such as benzene ring, naphthalene ring and thiophene ring, and aromatic rings such as cyclohexane, And a divalent substituent obtained by removing two of them.

The structural unit represented by the above formula (13) is preferably a repeating unit of a polyalkylene glycol, a repeating unit of a polyester diol and a repeating unit of a polycarbonate diol, and is preferably an alkylene oxide unit having 2 to 4 carbon atoms , Specifically an ethylene oxide unit and a propylene oxide unit, but there is no particular limitation on the repeating unit of the polyalkylene glycol having any hydrocarbon group, the repeating unit of the polyester diol and the repeating unit of the polycarbonate diol.

In the structural unit represented by the above formula (13), an acid group such as a phosphoric acid group, a sulfonic acid group or a carboxy group or a salt thereof may be contained in the structure.

When the total amount of all the constituent units constituting the polymer (B) is 100 mol%, the content of the structural unit represented by the above formula (13) is preferably 0.1 to 90 mol%. When the content of the structural unit represented by the above formula (13) is 0.1 mol% or more, an electrode having excellent flexibility can be formed. Particularly, when the structural unit represented by the above-mentioned general formula (13) is derived from a bifunctional monomer which undergoes a crosslinking reaction such as a diacrylate described below, in order to suppress gelation when the polymer (B) 0.1 to 30 mol% is preferable.

The structural unit represented by the above formula (13) may be introduced into the polymer (B) from any source. For example, the polymerization may be carried out using a monomer (compound) having a substituent having a structural unit represented by the above formula (13), or a polymerization initiator containing a substituent having a structural unit represented by the above formula Or the structural unit represented by the above formula (13) may be introduced after polymerization.

The structural unit represented by the formula (13) is preferably derived from at least one compound selected from the group consisting of compounds represented by the following formulas (14) to (16). On the other hand, the compound represented by the following general formula (14) is mono (meth) acrylate, and the compound represented by the following general formula (15) is a di (meth) acrylate and these are monomers which are raw materials of the polymer (B). On the other hand, the compound represented by the following formula (16) is a polymerization initiator used in the polymerization of the polymer (B).

[Chemical Formula 14]

[Chemical Formula 15]

[Chemical Formula 16]

In the above formula (14), R ¹⁶ is a hydrogen atom or a methyl group.

R ¹⁷ is a hydrogen atom or a monovalent substituent. As the monovalent substituent, a linear or branched monovalent hydrocarbon group; A monovalent substituent group obtained by removing one hydrogen from any carbon atom of the aromatic ring or alicyclic ring; An acidic group and a salt thereof, and they may be single or may be bonded to another substituent, and the skeleton or substituent may contain a hetero atom. Specifically, linear or branched monovalent hydrocarbon groups such as an alkyl group having 1 to 20 carbon atoms; A monovalent substituent group obtained by removing one hydrogen from any carbon atom of an alicyclic ring such as an aromatic ring such as a benzene ring, a naphthalene ring or a thiophene ring, or a cyclohexane; An acid group such as a phosphoric acid group, a carboxy group and a sulfonic acid group, and salts thereof.

X ¹¹ is a divalent substituent having the structural unit represented by the above formula (13). Specifically, it is a divalent substituent comprising at least one selected from the group consisting of repeating units of polyalkylene glycol, repeating units of polyester diol, and repeating units of polycarbonate diol. Among them, those having repeating units of polyalkylene glycol are preferable.

The form of X ¹¹ may be a repetition of a single structural unit or a repetition of two or more structural units. When the form of X ¹¹ is a repetition of two or more structural units, the alignment method of the structural units is not particularly limited, and each structural unit may be present at random, each structural unit may be present as a block, Each structural unit may alternatively exist.

Examples of the compound represented by the formula (14) (hereinafter referred to as &quot; monomer (b4) &quot;) include those shown below.

R ¹⁶ is a methyl group, R ¹⁷ is a hydrogen atom, X ¹¹ is a repeating unit of ethylene glycol, Blemmer E (repeating unit of ethylene glycol is 1), Blemer PE series (for example, repeating units of ethylene glycol are weak 2 to 8).

R ¹⁶ is a methyl group, R ¹⁷ is a hydrogen atom, X ¹¹ is a repeating unit of propylene glycol, Blemer P (repeating unit is 1), Blemmer PP series (for example, repeating units are about 4 to 13).

Blemer 50PEP-300 wherein R ¹⁶ is a methyl group, R ¹⁷ is a hydrogen atom, X ¹¹ is a repeating unit of ethylene glycol and propylene glycol (the repeating unit of ethylene glycol is about 3.5, the repeating unit of propylene glycol is about 2.5) 70PEP-350B (the repeating unit of ethylene glycol is about 5, and the repeating unit of propylene glycol is about 2).

Blemer 55PET-800 wherein R ¹⁶ is a methyl group, R ¹⁷ is a hydrogen atom, and X ¹¹ is a repeating unit of ethylene glycol and butylene glycol (the repeating unit of ethylene glycol is about 10 and the repeating unit of butylene glycol is about 5).

Blemer AE series in which R ¹⁶ is a hydrogen atom, R ¹⁷ is a hydrogen atom, and X ¹¹ is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is about 2 to 10).

Blemer AP series in which R ¹⁶ is a hydrogen atom, R ¹⁷ is a hydrogen atom, and X ¹¹ is a repeating unit of propylene glycol (for example, repeating units of propylene glycol is about 3 to 9).

Blemer PME series in which R ¹⁶ is a methyl group, R ¹⁷ is a methyl group, and X ¹¹ is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is about 2 to 90).

AM-130G in which R ¹⁶ is a methyl group, R ¹⁷ is a methyl group, and X ¹¹ is a repeating unit of ethylene glycol (for example, the repeating unit of ethylene glycol is about 13).

Blemer 50POEP-800B wherein R ¹⁶ is a methyl group, R ¹⁷ is CH ₂ CH (C ₂ H ₅ ) C ₄ H ₉ and X ¹¹ is a repeating unit of ethylene glycol and propylene glycol (the repeating unit of ethylene glycol is about 8, propylene The repeating unit of glycol is about 6).

Blemer PSE-1300 in which R ¹⁶ is a methyl group, R ¹⁷ is an octadecyl group, and X ¹¹ is a repeating unit of ethylene glycol (the repeating unit of ethylene glycol is about 30).

Blemer PAE series wherein R ¹⁶ is a methyl group, R ¹⁷ is a phenyl group, and X ¹¹ is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is 1 or 2).

R ¹⁶ is a hydrogen atom, R ¹⁷ is a substitution of one of the hydrogen atoms of the phenyl group with a nonyl group, and Blemer ANP-300 wherein X ¹¹ is a repeating unit of propylene glycol (the repeating unit of propylene glycol is about 5).

Blemer AAE series wherein R ¹⁶ is a hydrogen atom, R ¹⁷ is a phenyl group, and X ¹¹ is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is about 1 to 5.5).

Methacryloyloxyethyl phosphate in which R ¹⁶ is a hydrogen atom, R ¹⁷ is a phosphoric acid group, and X ¹¹ is a repeating unit of ethylene glycol (the repeating unit of ethylene glycol is 1).

These monomers (b4) may be used singly or in combination of two or more kinds.

An example of the structural formula of the above-mentioned monomer (b4) is shown below.

In Formula 15, R ¹⁸ and R ¹⁹ are each independently a hydrogen atom or a methyl group. X ¹² is a divalent substituent having a structural unit represented by the above formula (13). Specifically, it is a divalent substituent comprising at least one selected from the group consisting of repeating units of polyalkylene glycol, repeating units of polyester diol, and repeating units of polycarbonate diol. Among them, those having repeating units of polyalkylene glycol are preferable.

The form of X ¹² may be a repetition of a single structural unit or a repetition of two or more structural units. When the form of X ¹² is a repetition of two or more structural units, the alignment method of the structural units is not particularly limited, and each structural unit may be present at random, each structural unit may exist as a block, Each structural unit may alternatively exist.

Examples of the compound represented by the formula (15) (hereinafter referred to as &quot; monomer (b5) &quot;) include the following compounds.

A blemer PDE series wherein R ¹⁸ is a methyl group, R ¹⁹ is a methyl group, and X ¹² is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is about 2 to 14).

Blemer ADE series wherein R ¹⁸ is a hydrogen atom, R ¹⁹ is a hydrogen atom, and X ¹² is a repeating unit of ethylene glycol (for example, repeating units of ethylene glycol is about 4 to 14).

A blemer PDP series in which R ¹⁸ is a methyl group, R ¹⁹ is a methyl group, and X ¹² is a repeating unit of propylene glycol (for example, the repeating unit of propylene glycol is about 7 to 12).

Blemmer ADP series wherein R ¹⁸ is a hydrogen atom, R ¹⁹ is a hydrogen atom, and X ¹² is a repeating unit of propylene glycol (for example, the repeating unit of propylene glycol is about 6).

Blemmer ADT series wherein R ¹⁸ is a hydrogen atom, R ¹⁹ is a hydrogen atom, and X ¹² is a repeating unit of butylene glycol (for example, repeating units of butylene glycol is about 3).

R ¹⁸ is a methyl group, R ¹⁹ is a methyl group, X ¹² is an ethylene glycol repeating units, and _{-C 6 H 4 -C (CH 3} ) 2 -C 6 H 4 of - the blade Murray PDBE series (for example, ethylene glycol containing Repeating units of about 4 to 30).

A bromether PDBP series in which R ¹⁸ is a methyl group, R ¹⁹ is a methyl group and X ¹² is a propylene glycol repeating unit and -C ₆ H ₄ -C (CH ₃ ) ₂ -C ₆ H ₄ - (for example, Repeat units are about 10).

An example of the structural formula of the above-mentioned monomer (b5) is shown below.

As the monomer (b5), an acrylic ester PBOM (polybutylene glycol dimethacrylate, manufactured by Mitsubishi Rayon Co., Ltd., X ^{12 having} a mass average molecular weight (Mn ) = 650), KPBM (dimethacrylate of the polyester of 2-butyl-2-ethyl-1,3-propanediol and adipic acid as repeating units, Mn of X ¹² = 1800); Blemer PDT-650 (polytetramethylene glycol dimethacrylate, tetramethylene glycol repeating unit of 9 and X ¹² of Mn = 648) manufactured by NOF Corporation, Blemer 40PDC1700B (polyethylene glycol and polypropylene Dimethacrylate of a random copolymer of glycols, Mn of X ¹² = 1700); NK ester A-PTNG65 (polyethylene glycol diacrylate, repeating unit of ethylene glycol is 9 and Mn of X ¹² = 600) manufactured by Shin-Nakamura Chemical Co., Ltd., NK ester A- 600 (polyethyleneglycol diacrylate, repeat units of ethylene glycol is 14, the X ¹² Mn = 600), NK ester a-1000 (the repeating unit of polyethylene glycol diacrylate, ethylene glycol 23, X ¹² Mn = 1000 ), NK ester APG-700 (polypropylene glycol diacrylate, repeating unit of propylene glycol is 12, Mn of X ¹² = 700), NK ester 14G (polyethylene glycol dimethacrylate, ethylene glycol repeating unit is about 14 , Mn of X ¹² = 600), NK ester 23G (polyethylene glycol dimethacrylate, repeating units of ethylene glycol being 23, Mn of X ¹² = 1000); UH-100DM (polyhexane carbonate diol dimethacrylate, Mn of X ¹² = 800) manufactured by Ube Industries, Ltd. can be used.

These monomers (b5) may be used alone or in combination of two or more.

In the above formula (16), A ¹¹ and A ¹² each independently represent a monovalent substituent having the structural unit represented by the above formula (13).

As the polymerization initiator represented by the above formula (16), for example, an azo type polymerization initiator comprising a polyethylene glycol unit can be mentioned. Among them, polymeric azo initiators "VPE-0201", "VPE-0401" and "VPE-0601" each containing a polyethylene glycol (PEG) unit manufactured by Wako Pure Chemical Industries, Ltd. desirable. These are compounds in which A ¹¹ and A ¹² in the above formula (16) are repeating units of polyethylene glycol.

These polymerization initiators may be used alone or in combination of two or more.

As an example of the polymerization initiator represented by the above formula (16), the structural formula is shown below.

On the other hand, VPE-0201 manufactured by Wako Pure Chemical Industries, Ltd. has a molecular weight of polyethylene glycol unit of about 2000, VPE-0401 has a molecular weight of polyethylene glycol unit of about 4000, VPE-0601 has a molecular weight of polyethylene glycol unit of about 6000 .

In the formula (31), R ³¹ and R ³² are each independently a divalent substituent, R ³³ is a monovalent substituent, and any of R ³¹ to R ³³ has a vinyl group structure. s and t are each independently 0 or 1;

Examples of the monovalent and divalent substituents include straight, branched or cyclic hydrocarbon groups of 1 to 20 carbon atoms, groups in which one or two or more carbon atoms constituting the hydrocarbon group are substituted with hetero atoms such as oxygen, And the like. The hydrocarbon group may be substituted with at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, a carbonyl group, an aldehyde group, a primary to tertiary amino group, a nitro group, a cyano group, an acetal group, a thiol group, a thioether group, May be included. In the structure of R ³¹ to R ³³ , an acidic group such as a phosphoric acid group, a sulfonic acid group or a carboxy group, a salt thereof, or a basic group such as an amino group or a salt thereof may be contained.

As the vinyl group structure of any one of R ³¹ to R ³³ , a vinyl group structure represented by the following general formula (32) or (33) is preferable from the viewpoint of enhancing water solubility.

In the general formula (32), R ³⁴ is a hydrogen atom or a methyl group.

In the above formula (33), R ³⁵ is a hydrogen atom or a methyl group.

As the vinyl group structure, the vinyl group structure represented by the above formula (32) is more preferable, and among these, a vinyl group structure in which R ³⁴ is a hydrogen atom is preferable. In particular, if R ³¹ or R ³² has a case, R ³¹ or R ³² as by nilri dengi, vinyl-alkylene groups are preferred, and R ³³ is a vinyl group structure having a vinyl group structure, as the R ³³ is preferably a vinyl.

Examples of the compound represented by the above formula (31) (hereinafter referred to as "monomer (b7)") include N-vinyl-2-pyrrolidone, N-vinyl-2-caprolactam, Pyrrolidone, N-isopropranyl-2-caprolactam, and the like. Of these, N-vinyl-2-pyrrolidone is preferable.

When all the constituent units constituting the polymer (B) are 100 mol%, the content of the structural unit derived from the compound represented by the above formula (31) is preferably 0.1 to 50 mol%, more preferably 0.1 to 20 mol% , More preferably from 0.1 to 10 mol%. When the content of the structural unit derived from the compound represented by the above formula (31) is 0.1 mol% or more, the dispersibility of the slurry composition can be improved.

The polymer (B) contains, if necessary, units other than the structural units represented by the above formulas (11), (12) and (13) and the structural units derived from the compound represented by the above formula It may be.

(Hereinafter referred to as &quot; monomer (b8) &quot;) to be a monomer of any unit origin is not particularly limited as long as it can be copolymerized with monomers (b1), (b2), (b4), (b5) and , Such as acrylonitrile, methacrylonitrile,? -Cyanoacrylate, dicyanobonylidene, and fumaronitrile ethyl; Halogenated vinyl monomers such as vinyl chloride, vinyl bromide, and vinylidene chloride; Carboxy group-containing monomers such as itaconic acid and crotonic acid, and salts thereof; Aromatic vinyl monomers such as styrene and? -Methylstyrene; Maleimides such as maleimide and phenylmaleimide; (Meth) allylsulfonic acid, vinyl monomers containing sulfonic acid groups such as (meth) allyloxybenzenesulfonic acid and styrenesulfonic acid, and salts thereof; Phosphoric acid group-containing vinyl monomers and salts thereof; And vinyl acetate.

These monomers (b8) may be used singly or in combination of two or more kinds.

When the total amount of all the constituent units constituting the polymer (B) is 100 mol%, the content of arbitrary units is preferably 0 to 49 mol%, more preferably 0 to 20 mol%. When the content of the optional unit is within the above range, deterioration of the battery performance can be suppressed.

In the binder resin of the second aspect of the present invention, it is preferable that the structural unit represented by Chemical Formula 12 and / or Chemical Formula 13 is derived from a monomer (b) satisfying the following conditions, .

The glass transition temperature of the homopolymer of the monomer (b) ≤ the glass transition temperature of the homopolymer having the structural formula (11) as the structural unit

On the other hand, the glass transition temperature is the glass transition temperature of a homopolymer of each monomer, which is described in Polymer Handbook Fourth Edition (A WiLEY-INTERSCIENCE PUBLICATION). For monomers having no substrate in the Polymer Handbook, numerical values obtained under the same measurement conditions as the homopolymer of the monomer (b) and the homopolymer having the structural formula (11) as the structural unit can be used. As the analysis method, a value obtained by a known measurement method such as differential scanning calorimetry may be used. The monomer (b) satisfying the above conditions may form an acidic or basic salt.

The glass transition temperature of the homopolymer of the monomer (b) used in the present invention is preferably 110 占 폚 or lower, more preferably 50 占 폚 or lower, from the viewpoint of obtaining an electrode having more flexibility.

On the other hand, the glass transition point of poly N-vinylformamide by differential scanning calorimetry is 126 ° C. The conditions at this time are as follows.

Device: DSC7 (manufactured by PerkinElmer Inc.)

· Measured under a nitrogen flow at a heating rate of 10 ° C / min

Specific examples of the monomer (b) include the following monomers, but are not limited thereto. () Is the glass transition temperature of a homopolymer of each monomer described in Polymer Handbook Fourth Edition (A WiLEY-INTERSCIENCE PUBLICATION).

Examples of the monomer (b) include methyl acrylate (10 ° C), butyl methacrylate (20 ° C), 2-ethyl butyl acrylate (-50 ° C), 3-methoxypropyl acrylate Butyl acrylate (-54 ° C), hexyl acrylate (-57 ° C), 2-methoxyethyl acrylate (-50 ° C), and acrylic acid (108 ° C) have.

NK ester AM-90G (methoxypolyethylene glycol # 400 acrylate), NK ester AMP-20GY (phenoxypolyethylene glycol acrylate), NK ester A-SA (trade name) manufactured by Shin Nakamura Chemical Industry Co., (2-acryloyloxysuccinate), NK ester A-200 (polyethylene glycol # 200 diacrylate), NK ester S (stearyl acrylate), NK ester SA (2-methacryloyloxyethyl stearate Cinnamate) can be used.

In addition, it is preferable that the structural unit represented by Chemical Formula 12 and / or Chemical Formula 13 has an acidic group or a salt thereof, and the binding property of the compound layer to the current collector is improved.

The polymer (B) is a polymer having a structural unit represented by the general formula (11), a structural unit represented by the general formula (12), a structural unit represented by the general formula (13) It is preferable that the polymer is a polymer having two or more different structural units represented by the above-mentioned formula (12), and an electrode having more excellent flexibility is obtained, and the binding property is also improved.

The polymer (B) is obtained by polymerizing at least one monomer (b1), a monomer (b2), a monomer (monomers (b4) and (b5) And, if necessary, copolymerizing the monomer (b8); At least one of the monomer (b1), the monomer (b2), the monomer (monomers (b4) and (b5)) to be the origin of the structural unit represented by the above formula (13), and the monomer (b7) (b8) with a polymerization initiator represented by the above formula (16); And a method of polymerizing or copolymerizing the monomer (b1) and, if necessary, the monomer (b2), the monomer (b7) and the monomer (b8) using the polymerization initiator represented by the above formula (16). The polymerization method is not particularly limited, and solution polymerization, suspension polymerization, emulsion polymerization and the like can be selected depending on the type of the monomer to be used and the solubility of the resulting polymer (B).

For example, when the monomer to be used is soluble in water and the resulting polymer (B) also has sufficient affinity for water, aqueous solution polymerization may be used. The aqueous solution polymerization is a method of obtaining the polymer (B) by dissolving the monomer and the water-soluble polymerization initiator as raw materials in water and heating.

When the solubility of the monomer to be used in water is small, suspension polymerization, emulsion polymerization and the like can be used. Emulsion polymerization is a method in which a monomer, an emulsifier, a water-soluble polymerization initiator or the like serving as a raw material is added to water and heated under stirring to obtain a polymer (B).

After the polymerization, the polymer (B) in powder form is obtained by filtration, centrifugal separation, heat drying, vacuum drying and water removal in combination.

The molecular weight of the polymer (B) is not particularly limited, but the viscosity average molecular weight (Mv) is preferably 10,000 to 2,000, more preferably 100,000 to 1,500,000, still more preferably 500,000 to 1,000,000, Is particularly preferable. If the lower limit is above the lower limit, the binding property is higher. If the lower limit is below the upper limit, the water-solubility becomes higher and the dispersibility of the conductive auxiliary becomes better.

The viscosity average molecular weight (Mv) is calculated from the viscosity of the aqueous solution of the polymer (B) as a viscosity-converted molecular weight using poly N-vinylformamide (hereinafter referred to as PNVF) as a standard material. The viscosity average molecular weight can be calculated by the same method as that described in the first aspect.

The binder resin of the second aspect of the present invention may be composed only of the polymer (B), but may contain a polymer other than the polymer (B) as long as the effect of the present invention is not impaired.

Examples of the other polymer include polyacrylic acid and salts thereof, polyvinyl alcohol and polyacrylamide. These may be used alone or in combination of two or more.

The content of the other polymer in 100% by mass of the binder resin is preferably 0 to 50% by mass.

Examples of the form of the binder resin include a powder phase, a doped phase dissolved or dispersed in a solvent such as water, and the like. From the viewpoints of stability during storage and distribution, economic efficiency, and easiness of handling, powdery form is preferable for storage and distribution.

The binder resin according to the second aspect of the present invention described above is a derivative derived from the structural unit represented by the formula (12) in addition to the monomer (b1) which is an origin of the structural unit represented by the formula (11) At least one of the monomer (b2), the monomer (monomer (b4), (b5), etc.) to be the origin of the structural unit represented by the formula (13) and the compound represented by the formula (31) (B) obtained by copolymerizing these monomers (b) and (b), or a polymerization initiator represented by the above-mentioned formula (16), and polymerizing at least the monomer (b1). The polymer (B) is water-soluble and comprises a structural unit represented by the formula (11), a structural unit represented by the formula (12), a structural unit represented by the formula (13) , The electrode produced using the polymer (B) has excellent flexibility.

Therefore, the binder resin of the second embodiment of the present invention including the polymer (B) is water-soluble and can form an electrode having excellent flexibility. More specifically, when flexibility evaluation of the electrode is carried out by the following flexibility test, it is possible to form an electrode having no change in the material mixture layer.

Here, the phrase &quot; there is no change in the mixed layer &quot; means a state in which the horizontal stripes enter the mixed layer or cracks or peeling do not occur.

(Flexibility test)

The binder resin for the non-aqueous secondary battery electrode and water are kneaded. The active material is added and kneaded. When the electrode is a positive electrode, a conductive auxiliary agent is added and kneaded, followed by adjustment to water to a coating viscosity to obtain a slurry composition. The blending amount is 2 parts by mass of the binder resin for the non-aqueous secondary battery electrode, and 5 parts by mass of the conductive auxiliary for 100 parts by mass of the active material.

The obtained slurry composition is coated on a current collector and dried to obtain an electrode in which a mixed layer having a thickness of 20 to 200 mu m is formed on the current collector.

The obtained electrode was cut into 3 cm in width and 5 cm in length, and used as a test piece.

A mandrel having a diameter of 8 mm was placed on the current collecting surface of the obtained test piece and the state of the mixed layer was observed when the test piece was bent so that the current collecting surface was in the inside in the humidity of 10% To evaluate the flexibility of the electrode.

The polymer (B) is a polymer having at least the structural unit represented by the general formula (11) and the structural unit represented by the general formula (12), or the structural unit represented by the general formula (11) , The binding property of the binder resin is also improved.

«Binder resin composition for non-aqueous secondary battery electrode»

The binder resin composition for a nonaqueous secondary battery electrode of the second aspect of the present invention (hereinafter simply referred to as a binder resin composition) contains the binder resin of the second aspect of the present invention described above.

Examples of the form of the binder resin composition include a powder phase, a doped phase dissolved or dispersed in a solvent such as water, and the like. From the viewpoints of stability during storage and distribution, economic efficiency, and easiness of handling, powdery form is preferable for storage and distribution.

The content of the binder resin in the powdery binder resin composition is preferably 50% by mass or more, more preferably 80% by mass or more, and may be 100% by mass. If the lower limit value is not less than the lower limit, the effect of the present invention is remarkably exhibited.

The binder resin composition of the second aspect of the present invention may contain a binder resin (other binder resin) other than the binder resin of the second aspect of the present invention, a viscosity adjusting agent, a binding property An additive such as an improving agent, a dispersing agent and the like may be contained.

As other binder resins, there may be mentioned other binder resins exemplified in the description of the binder resin composition of the first embodiment, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoro Fluorine resins such as alkyl vinyl ether copolymers (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and ethylene-tetrafluoroethylene copolymer (ETFE).

As the viscosity adjusting agent, the same as the viscosity adjusting agent exemplified above in the description of the binder resin composition of the first embodiment can be mentioned.

The additive such as the viscosity adjusting agent finally remains on the electrode. Therefore, it is preferable that the additive is not added as much as possible. However, when added, it is preferable to use an additive having electrochemical stability.

When the binder resin composition contains an additive such as a viscosity adjusting agent, the content thereof is preferably 50% by mass or less when the binder resin composition is 100% by mass. However, the content of the additive is preferably as small as possible from the viewpoint of further improving battery performance.

The binder resin composition can be produced by a known method. For example, the binder resin of the second aspect of the present invention in the form of a powder and, if necessary, a powdery additive may be powder-mixed, or the binder resin of the second aspect of the present invention in the form of a powder and, if necessary, the powdery additive may be dispersed in water .

The binder resin composition of the second aspect of the present invention described above contains the binder resin of the second aspect of the present invention described above, so that an electrode that is water-soluble and has excellent flexibility can be formed.

In particular, when the polymer (B) contained in the binder resin is a polymer having at least the structural unit represented by the formula (11) and the structural unit represented by the formula (12), or the structural unit represented by the formula , The binding property of the binder resin composition is also improved.

&Quot; Slurry composition for non-aqueous secondary battery electrode &

The slurry composition for a nonaqueous secondary battery electrode according to the second aspect of the present invention (hereinafter, simply referred to as a slurry composition) is obtained by mixing the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention, An active material, and water.

The binder resin used in the slurry composition of the second aspect of the present invention is the binder resin of the second aspect of the present invention described above, and a detailed description thereof will be omitted. The binder resin composition used in the slurry composition of the second aspect of the present invention is the binder resin composition of the second aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the slurry composition of the second aspect of the present invention is not particularly limited, but is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass in the total solid content of the slurry composition (total components excluding the solvent) More preferable. If it is 0.01% by mass or more, the adhesiveness (tackiness) between the mixture layer and the current collector formed using the slurry composition becomes higher. When the amount is 15% by mass or less, the active material and optional components to be described later (for example, a conductive auxiliary agent) can be sufficiently contained.

The active material used in the slurry composition of the second aspect of the present invention is not particularly limited, and any known electrode material may be used depending on the application of the electrode to be manufactured using the slurry composition to any non-aqueous secondary battery.

For example, in the case of a lithium ion secondary battery, a material capable of attracting and desorbing lithium ions during charging and discharging is used as a positive electrode active material (positive electrode active material) rather than a negative electrode active material (negative electrode active material) .

Specific examples of the positive electrode active material and negative electrode active material include the same materials as the positive and negative electrode active materials exemplified above in the description of the slurry composition of the first embodiment. These positive electrode active materials and negative electrode active materials may be used singly or in combination of two or more.

In the lithium ion secondary battery, it is preferable to use a lithium-containing metal complex oxide as the positive electrode active material and graphite as the negative electrode active material. With such a combination, the voltage of the lithium ion secondary battery can be increased to 4V or more, for example.

The content of the active material in the slurry composition of the second aspect of the present invention is not particularly limited, but it is preferably 80 to 99.9 mass%, more preferably 85 to 99 mass% of the total solid content of the slurry composition (total components excluding the solvent) desirable. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. If it is 99.9 mass% or less, the adhesion (adhesion) between the mixture layer and the current collector is good.

As the solvent contained in the slurry composition of the second aspect of the present invention, at least water is used, but a mixed solvent of water and an organic solvent may be used. As the organic solvent, those that can be dissolved or dispersed uniformly in the binder resin are selected. Specific examples of the organic solvent include those similar to the organic solvents exemplified above in the description of the slurry composition of the first aspect. These organic solvents may be used alone or in combination of two or more.

Examples of the mixed solvent include a mixed solvent of water and an alcohol-based solvent, a mixed solvent of water and an NMP and an ester-based solvent, and a mixed solvent of water and an NMP and a grit-based solvent.

However, since the organic solvent has a high environmental load, it is preferable to use water alone as the solvent.

The content of the solvent in the slurry composition of the second aspect of the present invention may be the minimum amount required to maintain the binder resin or the binder resin composition in a dissolved or dispersed state at room temperature, but is preferably from 5 to 50 mass% And more preferably 40 mass%. The content of the solvent in the slurry composition is determined in consideration of the viscosity which is easily applied to the current collector when the slurry composition is formed using the slurry composition.

The slurry composition of the second aspect of the present invention may contain the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention, the active material, and components (optional components) other than the solvent .

Examples of optional components include conductive additives, antioxidants, thickeners, and the like.

Particularly, when the slurry composition of the second aspect of the present invention forms the mixture layer of the positive electrode or when the mixture layer of the negative electrode containing the metal fine particles such as silicon is formed, it is preferable that the slurry composition contains the conductive additive . By containing the conductive auxiliary agent, electrical contact between the active materials and between the active material and the metal fine particles can be improved, and battery performance such as discharge rate characteristics of the nonaqueous secondary battery can be further improved.

As the conductive auxiliary agent, those similar to those described above for the explanation of the slurry composition of the first embodiment may be mentioned. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the slurry composition of the second aspect of the present invention is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.1 to 7% by mass, in the total solid content (excluding the solvent) More preferable. If it is 0.01% by mass or more, the battery performance is higher. If it is 10% by mass or less, the adhesiveness (binding property) between the mixture layer and the current collector is good.

The slurry composition of the second aspect of the present invention is obtained by mixing the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention, the active material, the solvent and optional components (such as conductive additives) And then kneading them. The kneading can be carried out by a known method.

In preparing the slurry, the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention may be used in the form of powder as it is, or may be used in the form of a solution in advance of mixing with an active material or optional components To be used as a resin solution.

The slurry composition according to the second aspect of the present invention described above includes the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention, so that an electrode having excellent flexibility can be formed.

In particular, when the polymer (B) contained in the binder resin is a polymer having at least the structural unit represented by the formula (11) and the structural unit represented by the formula (12), or the structural unit represented by the formula , It is possible to form a mixed layer having excellent binding property to the current collector.

«Electrodes for non-aqueous secondary batteries»

An electrode for a secondary battery according to a second aspect of the present invention (hereinafter simply referred to as an electrode) comprises a current collector and a mixture layer provided on the current collector, The binder resin composition of the second embodiment of the present invention, and the active material.

The current collector may be a conductive material, and examples thereof include metals such as aluminum, copper, and nickel.

The shape of the current collector can be determined according to the shape of the target battery, and examples thereof include a thin film, a mesh, and a fibrous. Among them, a thin film is preferable.

The thickness of the current collector is not particularly limited, but is preferably 5 to 30 m, more preferably 8 to 25 m.

The binder resin used in the compounding layer is the binder resin of the second aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the mixed layer is not particularly limited, but is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass. If it is 0.01% by mass or more, the adhesiveness (tackiness) between the mixture layer and the current collector formed using the slurry composition of the second aspect of the present invention described above becomes higher. When the content is 15 mass% or less, the active material and optional components (for example, conductive additives) can be sufficiently contained, thereby improving battery characteristics.

As the active material to be used in the mixed layer, the same materials as the active materials exemplified above in the description of the slurry composition of the first embodiment can be mentioned.

The content of the active material in the mixed layer is not particularly limited, but is preferably 80 to 99.9 mass%, and more preferably 85 to 99 mass%. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. If it is 99.9 mass% or less, the adhesion (adhesion) between the mixture layer and the current collector is good.

In the case where the electrode of the second aspect of the present invention is a cathode or a cathode containing fine metal particles such as silicon, the mixture layer preferably contains a conductive auxiliary agent. By containing a conductive auxiliary agent, battery performance can be further improved.

As the conductive auxiliary agent, those similar to those described above for the explanation of the slurry composition of the first embodiment may be mentioned. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the mixed layer is not particularly limited, but is preferably 0.01 to 10% by mass, and more preferably 0.1 to 7% by mass. If it is 0.01% by mass or more, the battery performance is higher. If it is 10% by mass or less, the adhesiveness (binding property) between the mixture layer and the current collector is good.

The composite layer is formed by dissolving or dispersing the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention described above, the active material, and optional components (such as a conductive auxiliary agent) (Rolling step) of preparing a slurry composition of the present invention (slurry preparation step), applying the slurry composition to the current collector (coating step), drying it to remove the solvent .

When the current collector is in the form of a thin film or a network, the mixture layer may be provided on one side or both sides of the current collector.

The method of coating the slurry composition is not particularly limited as long as the slurry composition can be applied to the current collector in an arbitrary thickness. For example, in the description of the electrode of the first embodiment, .

The coating amount can be appropriately set in accordance with the thickness of the mixture layer to be formed.

The applied slurry composition is dried to remove the solvent to form a mixed layer.

The drying method is not particularly limited as long as the solvent can be removed. For example, in the explanation of the electrode of the first aspect, the same method as the drying method exemplified above can be mentioned.

After drying, the formed mixture layer may be rolled if necessary. By rolling, the area of the mixture layer can be widened and the thickness can be adjusted to an arbitrary thickness.

Examples of the rolling method include a method such as a die press or a roll press.

On the other hand, the obtained electrode may be cut to an arbitrary dimension.

The thickness of the compounded layer can be appropriately determined depending on the kind of the active material, but is preferably 20 to 200 m, more preferably 30 to 120 m.

The electrode of the second aspect of the present invention can be used for both the positive electrode and the negative electrode of the non-aqueous secondary battery. Particularly, it is suitable as an electrode for a lithium ion secondary battery.

The electrode according to the second aspect of the present invention described above is characterized in that since the binder resin comprising the binder resin of the second aspect of the present invention or the binder resin composition of the second aspect of the present invention is formed on the current collector, Do.

In particular, when the polymer (B) contained in the binder resin is a polymer having at least the structural unit represented by the formula (11) and the structural unit represented by the formula (12), or the structural unit represented by the formula , The binding property of the compounded layer to the current collector is also excellent.

«Non-aqueous secondary battery»

The non-aqueous secondary battery of the second aspect of the present invention (hereinafter, simply referred to as a battery) comprises the non-aqueous secondary battery electrode of the second aspect of the present invention described above.

The &quot; nonaqueous secondary battery &quot; is a nonaqueous electrolyte which does not contain water as an electrolyte and includes, for example, a lithium ion secondary battery. The nonaqueous secondary battery generally includes electrodes (positive electrode and negative electrode), a nonaqueous electrolyte, and a separator, for example, the same as the nonaqueous secondary battery exemplified above in the description of the battery of the first aspect.

As the non-aqueous electrolyte, an electrolytic solution obtained by dissolving a solid electrolyte in an organic solvent can be mentioned.

Examples of the organic solvent of the electrolytic solution include the same organic solvents as the electrolytic solution exemplified above in the description of the non-aqueous secondary battery of the first embodiment. These organic solvents may be used alone or in combination of two or more.

The solid electrolyte can be a known one depending on the kind of the non-aqueous secondary battery or the active material. For example, in the case of a lithium ion secondary battery, any of known lithium salts can be used, and the same as the solid electrolytes exemplified above in the description of the battery of the first aspect can be used.

As the electrolyte of the lithium ion secondary battery, it is preferable that LiPF ₆ is dissolved in a carbonate.

In the battery of the second aspect of the present invention, the electrode of the second aspect of the present invention is used for either or both of the positive electrode and the negative electrode.

When either the positive electrode or the negative electrode is the electrode of the second aspect of the present invention, a known electrode may be used as the other electrode.

As the separator, a known one can be used, and for example, the same as the separator exemplified above in the description of the battery of the first aspect can be used.

The manufacturing method of the battery of the second aspect of the present invention is not particularly limited and a known method can be adopted. For example, in the description of the battery of the first aspect, the same method as that of the lithium ion secondary battery described above .

On the other hand, since the electrode of the second aspect of the present invention is excellent in flexibility, it is easy to be wound or bent.

The shape of the battery may be a coin shape, a cylindrical shape, a square shape, or a flat shape.

The battery according to the second aspect of the present invention described above has the electrode of the second aspect of the present invention, and therefore has excellent battery performance. The reason for this is that the excellent cell performance is because the electrode is excellent in flexibility, so that it is difficult for the electrode to be broken even when stress is applied, and the binder resin is hardly eluted in the electrolyte solution. When the binding property to the current collector of the compounded layer is high, the battery performance is further improved.

The "third sun"

«Binder resin for non-aqueous secondary battery electrode»

The binder resin for a non-aqueous secondary battery electrode (hereinafter, simply referred to as a binder resin) of the third aspect of the present invention contains the following component (?) And / or component (?).

(?) Component (?) having a structural unit represented by the following formula (21) and a structural unit represented by the following formula (22).

(?): A mixture of a polymer (? 1) having a structural unit represented by the following formula (21) and a polymer (? 2) having a structural unit represented by the following formula (22).

The polymer (? 1) preferably has a structural unit represented by the following formula (21) in an amount of 10 mol% or more, more preferably 30 mol% or more, further preferably 50 mol% or more, desirable.

 The polymer (? 2) preferably has a structural unit represented by the following formula (22) in an amount of 10 mol% or more, more preferably 30 mol% or more, further preferably 50 mol% or more, desirable.

(β) is preferably a mixture of a polymer (β1) having 80 mol% or more of the structural unit represented by the following general formula (21) and a polymer (β2) having a structural unit represented by the following general formula Do.

The polymer (? 1) does not have a structural unit represented by the following chemical formula (22), and the polymer (? 2) does not have a structural unit represented by the following chemical formula (21).

[Chemical Formula 21]

[Chemical Formula 22]

In the formula (21), R ²¹ is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms.

Specific examples of the hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl and pentyl groups. The hydrocarbon group may also be a linear chain substituent.

From the viewpoint of enhancing the water-solubility of the binder resin, it is preferable that the number of carbon atoms is smaller when R ²¹ is a hydrocarbon group, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is more preferable as R ²¹ , The atom is particularly preferred.

When the total amount of the constituent units constituting the binder resin is 100 mol%, the content of the structural unit represented by the formula (21) is preferably 0.1 to 99.9 mol%, more preferably 1 to 99 mol% And particularly preferably from 3 to 97 mol%. The greater the content of the structural unit represented by the above-mentioned formula (21), the better the bondability with the current collector becomes. In addition, excellent flexibility can be imparted to the electrode to be produced.

As the method for measuring the content of the structural unit represented by the formula (21) in the binder resin, the following colloid titration method can be suitably used.

The aqueous solution of the binder resin is precisely weighed, collected in a measuring flask, and then added with demineralized water. The aqueous solution of the binder resin is collected from the measuring flask by using a hole pipette, and then added with demineralized water. The pH is adjusted to 1 to 5 with 1N hydrochloric acid solution while checking with a pH meter.

Toluidine blue is added to the resulting test solution, and the solution is titrated with N / 400-polyvinylsulfate potassium sulfate solution. The point where the test liquid is discolored from blue to purple is taken as the end point. From the titration results, the content ratio of the structural unit represented by the above formula (21) is obtained.

Examples of the monomer derived from the structural unit represented by the formula (21) (hereinafter referred to as &quot; monomer (c1) &quot;) include vinylamine and allylamine.

In the above formula (22), R ²² and R ²³ are each independently a hydrogen atom or a hydrocarbon group of 1 to 5 carbon atoms.

Specific examples of the hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl and pentyl groups. The hydrocarbon group may also be a linear chain substituent.

From the viewpoint of increasing the water-solubility of the binder resin, it is preferable that R ²² and R ²³ are hydrocarbon groups with a small number of carbon atoms, and R ²² and R ²³ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, Or a methyl group is more preferable. Particularly, from the viewpoint of improving the water solubility, it is preferable that R ²² is a hydrogen atom and R ²³ is a hydrogen atom or a methyl group, and it is particularly preferable that R ²³ is a hydrogen atom.

When the total amount of the constituent units constituting the binder resin is 100 mol%, the content of the structural unit represented by the formula (22) is preferably 0.1 to 99.9 mol%, more preferably 1 to 99 mol% And particularly preferably from 3 to 97 mol%. As the content of the structural unit represented by the above formula (22) increases, the viscosity stability of the slurry composition containing the binder resin tends to be improved.

As the method for measuring the content of the structural unit represented by the formula (22) in the binder resin, the following ¹³ C-NMR measurement is suitable.

^{In the 13} C-NMR measurement, 15 mg of a binder resin powder obtained by lyophilizing an aqueous solution of the binder resin was added to 900 mg of a water solution containing 0.5% by mass of sodium 3- (trimethylsilyl) -1-propanesulfonate as a reference material The solution is placed in a test tube having a diameter of 5 mmφ so as to have a liquid height of about 5 cm and measured using a nuclear magnetic resonance apparatus under the following conditions, for example.

Measuring conditions:

· Observation frequency: 500 MHz (1H decoupling pulse mode)

· Measuring temperature: 30 ℃

· Number of accumulation: 10,000 times

On the other hand, in the Fourier transform of the FID signal, after the zero filling is performed twice, the broadening factor is set to 10 Hz.

In the obtained ¹³ C-NMR spectrum, the signal intensity of 160 to 165 ppm is regarded as the structural unit represented by the chemical formula 22, and the content ratio of the structural unit represented by the chemical formula 22 is obtained from the ratio of the integrated value of signal intensity.

Examples of the monomer (hereinafter referred to as &quot; monomer (c2) &quot;) originating from the structural unit represented by the formula (22) include N-vinylformamide and N-vinyl acetamide.

At least one of the polymer (?), The polymer (? 1) and the polymer (? 2) may have a structural unit represented by the following formula (23).

(23)

In the formula (23), R ²⁴ and R ²⁵ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms.

Specific examples of the hydrocarbon group include alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl and pentyl groups. The hydrocarbon group may also be a linear chain substituent.

From the viewpoint of enhancing the water-solubility of the binder resin, when R ²⁴ and R ²⁵ are hydrocarbon groups, the number of carbon atoms is preferably small. R ²⁴ and R ²⁵ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, Or a methyl group is more preferable. Particularly, in view of improving water solubility, it is preferable that R ²⁴ is a hydrogen atom and R ²⁵ is a hydrogen atom or a methyl group, and it is particularly preferable that R ²⁵ is a hydrogen atom.

When the total amount of all the constituent units constituting the binder resin is 100 mol%, the content of the structural unit represented by the formula (23) is preferably 0 to 50 mol%.

As a method for measuring the content of the structural unit represented by the above formula (23) in the binder resin, ¹³ C-NMR measurement as described above is suitable for explaining the method for measuring the content of the structural unit represented by the above formula (22).

In the obtained ¹³ C-NMR spectrum, the signal intensity of 150 to 155 ppm is regarded as the structural unit represented by the above formula (23), and the content ratio of the structural unit represented by the above formula (23) is obtained from the ratio of the integrated value of signal intensity.

The structural unit represented by the following general formula (23) is a structural unit in which, when any one of R ²¹ of the structural unit represented by the general formula ( ²¹ ) or R ²² of the structural unit represented by the general formula (22) is a hydrogen atom, , Water, and the like are removed.

The polymer (?), The polymer (? 1) and the polymer (? 2) may contain units other than the structural units represented by the above formulas (21) and (22)

(Hereinafter referred to as &quot; monomer (c3) &quot;) derived from an arbitrary unit is not particularly limited as long as it can be copolymerized with monomer (c1) and monomer (c2), and examples thereof include acrylonitrile, methacrylonitrile , cyanoized vinyl monomers such as? -cyanoacrylate, dicyanobonylidene, and fumaronitrile ethyl; (Meth) acrylates such as (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate and hexyl (meth) acrylate; (Meth) acrylic acid, itaconic acid, crotonic acid, and the like; Aromatic vinyl monomers such as styrene and? -Methylstyrene; Maleimides such as maleimide and phenylmaleimide; (Meth) allylsulfonic acid, vinyl monomers containing sulfonic acid groups such as (meth) allyloxybenzenesulfonic acid and styrenesulfonic acid, and salts thereof; (Meth) acryloyloxyethyl phosphate, 2- (meth) acryloyloxyethyl acid phosphate, monoethanolamine salt, diphenyl ((meth) acryloyloxyethyl) phosphate, (Meth) acrylate, acid phosphoxylpolyoxyethylene glycol mono (meth) acrylate, acid phosphoxylpolyoxypropylene glycol ((meth) acrylate, Methacrylate) and salts thereof; Dimethylaminoethyl (meth) acrylate; Vinyl acetate, and N-vinylpyrrolidone.

These monomers (c3) may be used singly or in combination of two or more kinds.

The mass average molecular weight of the polymer (a) is preferably from 5,000 to 10,000, more preferably from 10,000 to 750,000. If the mass average molecular weight of the polymer (?) Is not less than the lower limit value, the binding property becomes higher, and if it is lower than the upper limit value, the water solubility becomes better.

The mass average molecular weight of the polymer (? 1) is preferably 5,000 to 10,000, more preferably 10,000 to 750,000. When the mass average molecular weight of the polymer (? 1) is above the lower limit value, the binding property is higher, and when it is below the upper limit value, the water solubility becomes better.

The mass average molecular weight of the polymer (? 2) is preferably from 5,000 to 10,000, more preferably from 10,000 to 750,000. When the mass average molecular weight of the polymer (? 2) is not lower than the lower limit, the binding property is higher. When the weight average molecular weight is lower than the upper limit, the water solubility is better.

The mass average molecular weight of the polymer (?), The polymer (? 1) and the polymer (? 2) can be measured using gel permeation chromatography (GPC).

 The viscosity-converted molecular weight can be measured from the viscosity of each aqueous solution obtained by dissolving the polymer (?), The polymer (? 1) and the polymer (? 2) in water.

The content of the component (a) and component (b) in the binder resin is preferably such that the content of the structural units represented by the above formulas (21) and (22) falls within the above range.

The binder resin of the third aspect of the present invention may be composed only of the component (a) and / or the component (beta), but may be a mixture of the polymer (?) And the polymer (? .

In addition, it may contain a polymer other than the (?) Component and the (?) Component as long as the effect of the present invention is not impaired.

Examples of the other polymer include polyacrylic acid and its salt, polyvinyl alcohol and polyvinylpyrrolidone, and these may be used alone or in combination of two or more.

The other polymer may be used in an amount of 0 to 20 parts by mass when the total amount of the component (a) and the component (?) Is 100 parts by mass.

The polymer (? 1) is obtained by polymerizing a monomer raw material containing the monomer (c1).

The polymer (? 2) is obtained by polymerizing a monomer raw material containing the monomer (c2).

 The monomeric raw material of the polymer (? 1) and the polymer (? 2) may contain the monomer (c3) if necessary.

 The polymer (?) Is obtained by copolymerizing the monomer (c1), the monomer (c2) and, if necessary, the monomer (c3).

 The polymerization method is not particularly limited, and solution polymerization, suspension polymerization, emulsion polymerization, and the like can be selected depending on the type of the monomer to be used and the solubility of the resulting polymer.

For example, when the monomer to be used is soluble in water and the resulting polymer also has sufficient affinity for water, aqueous solution polymerization may be used. The aqueous solution polymerization is a method of obtaining a polymer by dissolving monomers and a water-soluble polymerization initiator as raw materials in water and heating them.

When the solubility of the monomer to be used in water is small, suspension polymerization, emulsion polymerization and the like can be used. The emulsion polymerization is a method of adding a monomer, an emulsifier, a water-soluble polymerization initiator or the like serving as raw materials to water and heating the mixture under stirring to obtain a polymer.

After the polymerization, the polymer is obtained by filtration, centrifugal separation, heat drying, vacuum drying and a combination of these to remove water.

The binder resin can be produced, for example, as follows.

When the binder resin contains the component (?), Another polymer may be added after obtaining the polymer (?) By the above-described method.

On the other hand, when the binder resin contains the component (?), It is also possible to obtain the polymer (? 1) and the polymer (? 2) by the aforementioned method and then mix them to give a mixture (?).

The binder resin is also obtained by hydrolyzing the polymer (? 2). According to this method, even when the monomer (c1) is unstable as a substance, the binder resin can be produced without being used for polymerization, and it becomes possible to provide the binder resin more stably.

(Corresponding to the polymer (?)) Having the constituent unit represented by the formula (21) and the constituent unit represented by the formula (22) by hydrolysis of the polymer (? 2) (Corresponding to the polymer (?)), The polymer having the constitutional unit represented by the formula (22) and the constitutional unit represented by the formula (23) (polymer ) Is obtained. When the hydrolysis proceeds almost 100%, a polymer (? 1) in which the structural unit of the formula (22) is substituted with the structural unit represented by the formula (21) is obtained.

Examples of hydrolysis methods include hydrolysis with an acid, hydrolysis with an alkali, and hydrolysis with application of heat, among which hydrolysis with an alkali is preferred.

Examples of the alkali (base) used for hydrolysis with alkali include metal hydroxides of Group 1 and Group 2 metals of the periodic table. Specific examples include sodium hydroxide, lithium hydroxide, potassium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide.

As the alkali, ammonia and alkyl derivatives of ammonia such as amines such as alkyl amines and allylamines are also suitable. Examples of such amines include triethylamine, monoethanolamine, diethanolamine, triethanolamine, morpholine, and aniline.

Among them, sodium hydroxide, lithium hydroxide and potassium hydroxide are preferable as the alkali.

When the polymer (? 2) is hydrolyzed using an acid or an alkali, the pH of the obtained reaction solution becomes acidic or alkaline, but it may be neutralized by neutralizing the reaction solution if necessary. The reaction liquid obtained by hydrolysis may be used as the binder resin as it is, but a polymer obtained by removing moisture from the reaction liquid may be used as the binder resin.

On the other hand, when the hydrolysis proceeds almost 100%, a polymer (? 1) having 90 mol% or more of the structural unit represented by the above formula (21) is obtained, and the polymer (? 2) is used as a binder resin .

Examples of the form of the binder resin include a powder phase, a granular phase, a doped phase dissolved or dispersed in a solvent such as water, and the like.

The binder resin of the third aspect of the present invention described above is a binder resin comprising the component (?) (That is, the polymer (?) Having the structural unit represented by Chemical Formula 22 and the structural unit represented by Chemical Formula 21 as the amide structural unit) (Or a mixture of a polymer (? 2) having a structural unit represented by the formula (22) and a polymer (? 1) having a structural unit represented by the formula (21). The polymer (?), The polymer (? 1) and the polymer (? 2) are water-soluble and excellent in flexibility. Moreover, an electrode manufactured using a polymer (?) Or a mixture of a polymer (? 1) and a polymer (? 2) is excellent in binding property, and a battery having the electrode has excellent battery characteristics.

Therefore, the binder resin of the third aspect of the present invention is water-soluble and can form an electrode having excellent flexibility. Specifically, when the flexibility test of the electrode is carried out by the flexibility test described in the second aspect, it is possible to form an electrode having no change in the mixture layer. Moreover, the binder resin of the third aspect of the present invention is also excellent in the binding property, and a battery excellent in battery characteristics can be obtained.

«Binder resin composition for non-aqueous secondary battery electrode»

The binder resin composition for a nonaqueous secondary battery electrode (hereinafter, simply referred to as a binder resin composition) of the third aspect of the present invention contains the binder resin of the third aspect of the present invention described above.

Examples of the form of the binder resin composition include a powder phase, a doped phase dissolved or dispersed in a solvent such as water, and the like.

The content of the binder resin in the binder resin composition is preferably 50% by mass or more, more preferably 80% by mass or more, and may be 100% by mass. If the lower limit value is not less than the lower limit, the effect of the present invention is remarkably exhibited.

The binder resin composition of the third aspect of the present invention may contain a binder resin (other binder resin) other than the binder resin of the third aspect of the present invention, a viscosity adjusting agent, a binding property An additive such as an improving agent, a dispersing agent and the like may be contained.

Examples of the other binder resins include the same ones as the above-mentioned other binder resins in the description of the binder resin compositions of the first and second aspects.

As the viscosity adjusting agent, the same as the viscosity adjusting agent exemplified above in the description of the binder resin composition of the first embodiment can be mentioned.

The additive such as the viscosity adjusting agent finally remains on the electrode. Therefore, it is preferable that the additive is not added as much as possible. However, when added, it is preferable to use an additive having electrochemical stability.

When the binder resin composition contains an additive such as a viscosity adjusting agent, the content thereof is preferably 50% by mass or less when the binder resin composition is 100% by mass. However, the content of the additive is preferably as small as possible from the viewpoint of further improving battery performance.

The binder resin composition can be produced by a known method. For example, the binder resin of the third aspect of the present invention and, if necessary, other binder resins in powder form or additives in powder form may be mixed in powder form, or the binder resin of the third aspect of the present invention and other binder resins And dispersing the powdery additive in water.

As described above, the binder resin composition of the third aspect of the present invention contains the binder resin of the third aspect of the present invention described above, so that an electrode that is water-soluble and has excellent flexibility can be formed. Moreover, the binder resin composition of the third aspect of the present invention is also excellent in binding property, and thus a battery excellent in battery characteristics can be obtained.

&Quot; Slurry composition for non-aqueous secondary battery electrode &

The slurry composition for a nonaqueous secondary battery electrode (hereinafter, simply referred to as a slurry composition) according to the third aspect of the present invention is obtained by mixing the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention, An active material, and water.

The binder resin used in the slurry composition of the third aspect of the present invention is the binder resin of the third aspect of the present invention described above, and a detailed description thereof will be omitted. The binder resin composition used in the slurry composition of the third aspect of the present invention is the binder resin composition of the third aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the slurry composition of the third aspect of the present invention is not particularly limited, but is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass, in the total solid content (excluding the solvent) More preferable. If it is 0.01% by mass or more, the adhesiveness (tackiness) between the mixture layer and the current collector formed using the slurry composition becomes higher. When the amount is 15% by mass or less, the active material and optional components to be described later (for example, a conductive auxiliary agent) can be sufficiently contained.

The active material used in the slurry composition of the third aspect of the present invention is not particularly limited, and any known electrode material may be used depending on the application for an electrode to be manufactured using the slurry composition for any non-aqueous secondary battery.

For example, in the case of a lithium ion secondary battery, a material capable of attracting and desorbing lithium ions during charging and discharging is used as a positive electrode active material (positive electrode active material) rather than a negative electrode active material (negative electrode active material) .

Specific examples of the positive electrode active material and negative electrode active material include the same materials as the positive and negative electrode active materials exemplified above in the description of the slurry composition of the first embodiment. These positive electrode active materials and negative electrode active materials may be used singly or in combination of two or more.

In the lithium ion secondary battery, it is preferable to use a lithium-containing metal complex oxide as the positive electrode active material and graphite as the negative electrode active material. With such a combination, the voltage of the lithium ion secondary battery can be increased to 4V or more, for example.

The content of the active material in the slurry composition of the third aspect of the present invention is not particularly limited, but is preferably 80 to 99.9 mass%, more preferably 85 to 99 mass% of the total solid content (excluding all of the solvent) of the slurry composition desirable. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. If it is 99.9 mass% or less, the adhesion (adhesion) between the mixture layer and the current collector is good.

As the solvent contained in the slurry composition of the third aspect of the present invention, at least water is used, but a mixed solvent of water and an organic solvent may be used. As the organic solvent, those that can be dissolved or dispersed uniformly in the binder resin are selected. Specific examples of the organic solvent include those similar to the organic solvents exemplified above in the description of the slurry composition of the first aspect. These organic solvents may be used alone or in combination of two or more.

Examples of the mixed solvent include a mixed solvent of water and an alcohol-based solvent, a mixed solvent of water and an NMP and an ester-based solvent, and a mixed solvent of water and an NMP and a grit-based solvent.

However, since the organic solvent has a high environmental load, it is preferable to use water alone as the solvent.

The content of the solvent in the slurry composition of the third aspect of the present invention may be such that the binder resin or the binder resin composition is maintained at a room temperature at a minimum amount necessary to maintain the dissolved or dispersed state, but is preferably 5 to 50 mass% And more preferably 40 mass%. The content of the solvent in the slurry composition is determined in consideration of the viscosity which is easily applied to the current collector when the slurry composition is formed using the slurry composition.

The slurry composition of the third aspect of the present invention may contain the binder resin of the third aspect of the invention or the binder resin composition of the third aspect of the present invention, the active material, and other components (optional components) other than the solvent .

Examples of optional components include conductive additives, antioxidants, thickeners, and the like.

Particularly, in the case where the slurry composition of the third aspect of the present invention forms the mixture layer of the positive electrode or when the mixture layer of the negative electrode containing fine metal particles such as silicon is formed, it is preferable that the slurry composition contains the conductive additive . By containing the conductive auxiliary agent, electrical contact between the active materials and between the active material and the metal fine particles can be improved, and battery performance such as discharge rate characteristics of the nonaqueous secondary battery can be further improved.

As the conductive auxiliary agent, those similar to those described above for the explanation of the slurry composition of the first embodiment may be mentioned. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the slurry composition of the third aspect of the present invention is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.1 to 7% by mass in the total solid content (excluding the solvent) More preferable. If it is 0.01% by mass or more, the battery performance is higher. If it is 10% by mass or less, the adhesiveness (binding property) between the mixture layer and the current collector is good.

The slurry composition of the third aspect of the present invention can be obtained by mixing the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention, the active material, the solvent and optional components (for example, And then kneading them. The kneading can be carried out by a known method.

In preparing the slurry, the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention may be used as it is or may be dissolved in a solvent before mixing with an active material or optional components (for example, a conductive auxiliary agent) It may be used as a resin solution.

The above-described slurry composition of the third aspect of the present invention includes the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention, so that an electrode having excellent flexibility can be formed. Moreover, the slurry composition of the third aspect of the present invention is also excellent in the binding property, and a battery excellent in battery characteristics can be obtained.

«Electrodes for non-aqueous secondary batteries»

An electrode for a secondary battery according to the third aspect of the present invention (hereinafter, simply referred to as an electrode) comprises a current collector and a mixture layer provided on the current collector, , The binder resin composition of the third aspect of the present invention, and the active material.

The current collector may be a conductive material, and examples thereof include metals such as aluminum, copper, and nickel.

The shape of the current collector can be determined according to the shape of the target battery, and examples thereof include a thin film, a mesh, and a fibrous. Among them, a thin film is preferable.

The thickness of the current collector is not particularly limited, but is preferably 5 to 30 m, more preferably 8 to 25 m.

The binder resin used in the compounded layer is the binder resin of the third aspect of the present invention described above, and a detailed description thereof will be omitted.

The content of the binder resin in the mixed layer is not particularly limited, but is preferably 0.01 to 15% by mass, more preferably 0.1 to 10% by mass. When the content is 0.01% by mass or more, the adhesiveness (tackiness) between the mixture layer and the current collector formed by using the slurry composition of the third aspect of the present invention described above becomes higher. When the content is 15 mass% or less, the active material and optional components (for example, conductive additives) can be sufficiently contained, thereby improving battery characteristics.

As the active material to be used in the mixed layer, the same materials as the active materials exemplified above in the description of the slurry composition of the first embodiment can be mentioned.

The content of the active material in the mixed layer is not particularly limited, but is preferably 80 to 99.9 mass%, and more preferably 85 to 99 mass%. When the content is 80% by mass or more, the function as a composite layer is sufficiently exhibited. If it is 99.9 mass% or less, the adhesion (adhesion) between the mixture layer and the current collector is good.

In the case where the electrode of the third aspect of the present invention is a cathode or a cathode containing fine metal particles such as silicon, the mixture layer preferably contains a conductive auxiliary agent. By containing a conductive auxiliary agent, battery performance can be further improved.

As the conductive auxiliary agent, those similar to those described above for the explanation of the slurry composition of the first embodiment may be mentioned. These conductive formulations may be used singly or in combination of two or more kinds.

The content of the conductive auxiliary agent in the mixed layer is not particularly limited, but is preferably 0.01 to 10% by mass, and more preferably 0.1 to 7% by mass. If it is 0.01% by mass or more, the battery performance is higher. If it is 10% by mass or less, the adhesiveness (binding property) between the mixture layer and the current collector is good.

The composite layer is obtained by dissolving or dispersing the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention described above, the active material, and optional components (such as a conductive auxiliary agent) (Rolling step) of preparing the slurry composition of the present invention (slurry preparation step), applying the slurry composition to the current collector (coating step), drying it to remove the solvent .

When the current collector is in the form of a thin film or a network, the mixture layer may be provided on one side or both sides of the current collector.

The method of coating the slurry composition is not particularly limited as long as the slurry composition can be applied to the current collector in an arbitrary thickness. For example, in the description of the electrode of the first embodiment, .

The coating amount can be appropriately set in accordance with the thickness of the mixture layer to be formed.

The applied slurry composition is dried to remove the solvent to form a mixed layer.

The drying method is not particularly limited as long as the solvent can be removed. For example, in the explanation of the electrode of the first aspect, the same method as the drying method exemplified above can be mentioned.

After drying, the formed mixture layer may be rolled if necessary. By rolling, the area of the mixture layer can be widened and the thickness can be adjusted to an arbitrary thickness.

 Examples of the rolling method include a method such as a die press or a roll press.

On the other hand, the obtained electrode may be cut to an arbitrary dimension.

The thickness of the compounded layer can be appropriately determined depending on the kind of the active material, but is preferably 20 to 200 m, more preferably 30 to 120 m.

The electrode of the third aspect of the present invention can be used for both the positive electrode and the negative electrode of the non-aqueous secondary battery. Particularly, it is suitable as an electrode for a lithium ion secondary battery.

The electrode according to the third aspect of the present invention described above is characterized in that the binder resin comprising the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention is formed on the current collector, Do. Moreover, the electrode of the third aspect of the present invention is also excellent in binding property to the current collector of the compounded layer. In addition, since the active material is hard to lose, the discharge capacity can be maintained high over a long period of time.

«Non-aqueous secondary battery»

The non-aqueous secondary battery (hereinafter, simply referred to as a battery) of the third aspect of the present invention comprises the non-aqueous secondary battery electrode of the third aspect of the present invention described above.

The &quot; nonaqueous secondary battery &quot; is a nonaqueous electrolyte which does not contain water as an electrolyte and includes, for example, a lithium ion secondary battery. The nonaqueous secondary battery generally includes electrodes (positive electrode and negative electrode), a nonaqueous electrolyte, and a separator, for example, the same as the nonaqueous secondary battery exemplified above in the description of the battery of the first aspect.

As the non-aqueous electrolyte, an electrolytic solution obtained by dissolving a solid electrolyte in an organic solvent can be mentioned.

 Examples of the organic solvent of the electrolytic solution include the same organic solvents as the electrolytic solution exemplified above in the description of the non-aqueous secondary battery of the first embodiment. These organic solvents may be used alone or in combination of two or more.

The solid electrolyte can be a known one depending on the kind of the non-aqueous secondary battery or the active material. For example, in the case of a lithium ion secondary battery, any of known lithium salts can be used, and the same as the solid electrolytes exemplified above in the description of the battery of the first aspect can be used.

As the electrolyte of the lithium ion secondary battery, it is preferable that LiPF ₆ is dissolved in a carbonate.

In the battery of the third aspect of the present invention, the electrode of the third aspect of the present invention is used for either or both of the positive electrode and the negative electrode.

When either the positive electrode or the negative electrode is the electrode of the third aspect of the present invention, a known electrode may be used as the other electrode.

As the separator, a known one can be used, and for example, the same as the separator exemplified above in the description of the battery of the first aspect can be used.

The method for producing the battery of the third aspect of the present invention is not particularly limited and a known method can be adopted. For example, in the description of the battery of the first aspect, similar to the method of manufacturing the lithium ion secondary battery described above .

On the other hand, the electrode of the third aspect of the present invention is easy to be wound or bent because of its excellent flexibility.

The shape of the battery may be a coin, a cylinder, a square, or a flat shape.

The battery according to the third aspect of the present invention described above has the electrode according to the third aspect of the present invention and therefore has excellent battery performance. The reason for this is that the excellent cell performance is because the electrode is excellent in flexibility, so that it is difficult for the electrode to be broken even when stress is applied, and the binder resin is hardly eluted in the electrolyte solution. Further, since the compounded layer contains the binder resin of the third aspect of the present invention or the binder resin composition of the third aspect of the present invention, the binding property of the compounded layer to the current collector is high, and the battery performance is further improved.

Example

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following description.

&Quot; Preparation of binder resin &quot;

&Lt; Preparation Example 1-1: Preparation of polymer (A-1) >

29.1 parts by mass of N-vinylformamide, 0.9 part by mass of acrylic acid with an aqueous solution of lithium hydroxide until pH = 9, and 0.8 part by mass of sodium acetate were added to 70 parts by mass of deionized water, 6.3 so as to obtain a monomer control solution.

 The monomer control solution was cooled to 5 캜, placed in an adiabatic reaction vessel equipped with a thermometer, and subjected to nitrogen aeration (exposure) for 15 minutes. Thereafter, 1500 ppm (a counter monomer) of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (VA-057 manufactured by Wako Pure Chemical Industries, Ltd.) (Monomer) was added as a 10 mass% aqueous solution, and further 200 ppm (a large monomer) of sodium hydrogen sulfite was added as an aqueous solution of 10 mass% .

After the inside temperature exceeded the peak, the mixture was further aged for one hour, and the gel was taken out, pulverized with a meat chopper, dried at 60 DEG C for 10 hours, and the obtained solid was pulverized to obtain a powdery polymer. This is referred to as Polymer (A-1).

On the other hand, the viscosity average molecular weight (Mv) of the polymer (A-1) calculated by the following method was 175,000 in terms of PNVF.

Calculation method of viscosity average molecular weight:

The intrinsic viscosity [] was calculated from the reduced viscosity (? Sp / C) of the aqueous solution of the polymer (A-1) and the formula of Huggins (? Sp / C = [?] + K '?? ² C). On the other hand, "C" in the above formula represents the concentration (g / dL) of the polymer in the aqueous solution of the polymer (A-1). A method for measuring the reduced viscosity of the aqueous solution of the polymer (A-1) is described below.

The viscosity average molecular weight (&quot; M &quot; in the formula) was calculated from the intrinsic viscosity [] obtained and the formula of Mark-Houwink ([eta] = KMa).

On the other hand, in the 1N saline solution, the parameters of PNVF are K = 8.31 x 10 ^-5 , a = 0.76, and K '= 0.31.

Method of measuring reduced viscosity:

First, the polymer was dissolved in 1N brine so that the concentration of the polymer (A-1) became 0.1% by mass to obtain an aqueous solution of the polymer (A-1). With respect to the aqueous solution of the obtained polymer (A-1), the dropping time (t ₁ ) at 25 캜 was measured using an Oswald viscometer.

Separately, as a blank, a dropping time (t ₀ ) at 25 ° C was measured for 1N saline using an Oswald viscometer.

From the obtained dropping time, the reduced viscosity was calculated by the following formula (iii).

_{ηsp / C = {(t 1} / t 0) -1} / C ··· (iii)

(In the formula (iii), C is the concentration (g / dL) of the polymer (A) in the aqueous solution of the polymer (A-1)

&Lt; Preparation Example 1-2: Preparation of Polymer (A-2) >

A powdery polymer was obtained in the same manner as in Production Example 1-1, except that 0.9 parts by mass of methyl acrylate was used instead of 0.9 part by mass of acrylic acid to which aqueous solution of lithium hydroxide was added until pH = 9. This is referred to as polymer (A-2).

On the other hand, the viscosity average molecular weight (Mv) of the polymer (A-2) calculated by the same method as that of the polymer (A-1) was 237,000 in terms of PNVF.

&Lt; Preparation Example 1-3: Preparation of Polymer (A-3) >

except that 0.9 part by mass of methoxypolyethylene glycol monomethacrylate ("Blemmer PME-200" manufactured by Nichiyu K.K.) was used instead of 0.9 part by mass of acrylic acid to which an aqueous solution of lithium hydroxide was added until the pH became 9, In the same manner as in Preparation Example 1-1, a powdery polymer was obtained. This is referred to as Polymer (A-3).

On the other hand, the viscosity average molecular weight (Mv) of the polymer (A-3) calculated by the same method as that of the polymer (A-1) was 290,000 in terms of PNVF.

&Lt; Polymer (A-5) >

Polyacrylic acid (mass average molecular weight (Mw) of about 1 million) produced by Wako Pure Chemical Industries, Ltd. was used as polymer (A-5).

[Examples 1-1 to 1-3 and Comparative Example 1-1]

The commercially available polyacrylic acid used as the polymer (A-1) to (A-3) and the polymer (A-5) obtained in Production Examples 1-1 to 1-3 was used as a binder resin, respectively.

I _S of the obtained binder resin was measured by the following procedure.

The various characteristics of the slurry composition for a positive electrode using each binder resin, the electrode (positive electrode) produced using the slurry composition for the positive electrode, and the secondary battery produced using the electrode (positive electrode) were evaluated in the following order. The results are shown in Table 1.

(1) Measurement of I _S of binder resin

To 0.5 parts by mass of the binder resin of Examples 1-1 to 1-3 and Comparative Example 1-1, 9.5 parts by mass of distilled water was added and stirred with a stirrer for 24 hours to prepare a sample solution.

The particle size distribution of the binder resin in the sample solution was measured under the following measurement conditions by using a thickener particle size analyzer FPAR-1000 (high sensitivity specification, thinning probe) manufactured by Otsuka Electronics Co., Ltd. .

Measurement conditions: The measurement was carried out at 25 캜 for a totalization time of 180 seconds three times, analyzed by the Marquardt method, and the particle diameter distribution data obtained by three measurements were averaged to obtain a particle diameter distribution of the binder resin . On the other hand, the particle diameter range was set to 0.1 nm to 1000000 nm.

From the measurement results, the sum I _s of the scattering intensities observed in the particle diameter range of 1 to 100 nm was determined.

(2) Preparation of slurry composition for positive electrode

100 parts by mass of lithium cobalt oxide (manufactured by Nippon Chemical Industrial Co., Ltd., "Cellseed C-5H") as an active material and 100 parts by mass of acetylene black (Denki Kagaku Kogyo Co., 5 parts by mass of "Denka Black" manufactured by Kagaku Kogyo Kabushiki Kaisha) and 2 parts by mass of the binder resin of Examples 1-1 to 1-3 and Comparative Example 1-1 were placed in a self-propelled stirrer (manufactured by Thinky Co., The mixture was mixed with 40 parts by mass of distilled water under the conditions of rotation of 1000 rpm and revolution of 2000 rpm using "Awatori Rentaro" to prepare a slurry composition for positive electrode.

(3) Evaluation of the tin-plasticity of the slurry composition for positive electrode

The shear rate-viscosity curve of the slurry composition for positive electrode prepared in (2) above was measured using a stress control rheometer AR550 manufactured by TA Instruments Waters LC. For the measurement, a cone plate having a diameter of 40 mm and an angle of 2 degrees was used, and the gap was 69 mm and the temperature was 25 ° C. Shear rate program, after varying the shear rate of 100sec ^-1 from 0.03sec ^-1 to measure the viscoelasticity, used a shear rate programs varying from a shear rate of 0.03sec ^-1 to measure the viscoelastic 100sec ^-1.

The shear rate by the program, performs a viscoelastic spectrometer at 25 ℃, shear rate when the shear rate was reached 100sec ^-1, with varying a shear rate to measure the viscoelastic 0.03sec ^-1 100sec ^-1 80sec from ^- the viscosity at ¹ (η _80), and shear rate to obtain a 0.1sec (η _{0. 1)} viscosity at ^-1 was obtained from η ₀ η _{0 0.1 0.1} of the binder resin by dividing the η ₈₀ / η _80.

The higher the value of η _{0 .1} / η _80, indicates that high thixotropic slurry composition. If the value of? _0.1 /? ₈₀ is 20 or more, it can be said that the tack firing is good.

(4) Production of electrode (anode)

The slurry composition for positive electrode prepared in (2) above was coated on an aluminum foil (19 cm x 25 cm, thickness 20 m) using a doctor blade, dried in a circulating hot air dryer at 80 ° C for 1 hour, To obtain an electrode (positive electrode) in which an aluminum foil was coated with a mixed layer having a thickness of 80 mu m by drying under reduced pressure at 100 DEG C for 12 hours.

(5) Evaluation of uniformity of the mixed layer

A vertical section of the electrode (anode) prepared in the above (4) was cut out using a section sample preparation apparatus ("SM-09010", manufactured by JEOL, Ltd.) A portion capable of simultaneously observing the adhered interface between the surface of the mixture layer and the aluminum foil and the compound layer was observed using an electron microscope (manufactured by Hitachi High-Technologies Corporation, &quot; SU1510 &quot; Three observations were made with the field of view. (SU) of the area occupied by the active material (lithium cobalt oxide) portion in the image of 10 m width x 50 m wide from the surface of the mixture layer toward the central portion of the mixture layer and the ratio (SB) of the area occupied by the active material (lithium cobalt oxide) in the image of 10 mu m in width and 50 mu m in width toward the center was measured by image analysis software (Image Cybernetics Co., "Image-Pro PLUS ver 4.5.0") And evaluated as follows.

?: The absolute value of (SU / SB) -1 is 0.1 or less.

?: The absolute value of (SU / SB) -1 is larger than 0.1 and not larger than 0.2.

X: Absolute value of (SU / SB) -1 is larger than 0.2.

The symbol &quot;? &Quot; indicates that the active material was homogeneously present throughout the mixture layer, and the paint characteristics were good.

(6) Production of secondary battery (2016 type coin battery)

The electrode (anode) prepared in (4) above and the commercially available metal lithium electrode (cathode) were opposed to each other with a separator (trade name: Celgard # 2400) interposed therebetween. A 2016 type coin cell was prepared using a 1M lithium hexafluorophosphate solution in which a mixture of ethylene carbonate / diethyl carbonate = 1/2 (volume ratio) was used as a nonaqueous electrolyte as a solvent.

(7) Measurement of initial battery capacity of secondary battery

The battery when the 2016 type coin battery manufactured in the above (6) was charged at 4.2 V with the charge / discharge rate of 0.5 C and the constant current method (current density: 0.6 mA / g-active material) The capacity was measured, and the measured value was taken as the initial battery capacity.

As shown in the results of Table 1, the binder resins of Examples 1-1 to 1-3 had a large value of I _S , and as a result, the resulting positive electrode slurry composition had good tin firing. The better the tic baking of the slurry composition, the better the storage stability of the slurry composition and the uniformity of the mix layer, and the battery characteristics are improved. Actually, the electrode (anode) obtained by using the slurry composition for positive electrode of each example had good uniformity of the mixed layer. In addition, the initial battery capacity of the secondary battery using the electrode (anode) was also good.

On the other hand, in the binder resin of Comparative Example 1-1, since the value of I _S was less than 30, the tin firing was poor.

&Lt; Preparation Example 1-5: Preparation of N-vinylformamide polymer >

30 parts by mass of N-vinylformamide (molecular weight: 71.08) was added to 70 parts by mass of deionized water to adjust the pH to 6.3 with phosphoric acid to obtain a monomer control solution.

The monomer control solution was cooled to 5 占 폚, placed in an adiabatic reaction vessel equipped with a thermometer, and subjected to nitrogen aeration for 15 minutes. Thereafter, 0.4 mass parts of an aqueous solution of 10 mass% of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (manufactured by Wako Pure Chemical Industries, Ltd., "VA-057" , Followed by 0.1 part by mass of a 10 mass% aqueous solution of t-butyl hydroperoxide and a 10 mass% aqueous solution of sodium hydrogensulfite, respectively, to perform polymerization.

After the inside temperature exceeded the peak, the gel was further aged for one hour, and the gel was taken out and pulverized with a meat chopper, followed by drying at 60 DEG C for 10 hours, and the resulting solid was pulverized to obtain a powdery N-vinylformamide polymer.

On the other hand, the viscosity average molecular weight (Mv) of the N-vinylformamide polymer calculated by the same method as that of the polymer (A-1) was 26.3 million in terms of PNVF.

&Lt; Preparation Example 1-6: Preparation of polymer (A-6) >

4 parts by mass of the N-vinylformamide polymer obtained in Preparation Example 1-5 was dissolved in 90 parts by mass of deionized water to prepare an aqueous polymer solution.

Separately, 0.24 parts by mass of an amount of lithium hydroxide monohydrate (molecular weight: 42) in which the molar ratio with respect to the N-vinylformamide polymer was 1% was dissolved in 6 parts by mass of deionized water to prepare an aqueous solution of lithium hydroxide monohydrate.

An aqueous solution of lithium hydroxide monohydrate was added to the aqueous polymer solution, stirred uniformly, and heated at 75 占 폚 for 5 hours to carry out a hydrolysis reaction. The reaction solution after the hydrolysis reaction was cooled to obtain an aqueous solution of the polymer (A-6).

10 parts by mass of an aqueous solution of the obtained polymer (A-6) was transferred to a 50 ml Nasar flask, and a degree of vacuum of 15 to 25 Pa was measured using a FT-1000 lyophilizer manufactured by Tokyo Rikakikai Co., , And freeze-dried at a trap temperature of -35 to -50 占 폚 for 48 hours to obtain a polymer (A-6).

PREPARATION EXAMPLE 1-7: Preparation of polymer (A-7)

Except that the amount of lithium hydroxide monohydrate added was changed to 4.7 parts by mass (the molar ratio of the lithium hydroxide monohydrate to the N-vinylformamide polymer of Production Example 1-5 was 20%) as in Production Example 1-6 To obtain a powdery polymer. This is referred to as Polymer (A-7).

PREPARATION EXAMPLE 1-8: Preparation of Polymer (A-8)

Except that the amount of lithium hydroxide monohydrate to be added was changed to 11.8 parts by mass (the molar ratio of the lithium hydroxide monohydrate to the N-vinylformamide polymer in Production Example 1-5 was 50%) as in Production Example 1-6 To obtain a powdery polymer. This is referred to as Polymer (A-8).

&Lt; Preparation Example 1-9: Preparation of Polymer (A-9) >

Was changed to 11.2 parts by mass of sodium hydroxide (molecular weight: 40) in place of lithium hydroxide monohydrate in an amount of 50% for the N-vinylformamide polymer of Production Example 1-5. 6, a powdery polymer was obtained. This is referred to as Polymer (A-9).

Examples 1-4 to 1-7 &quot;

The polymers (A-6) to (A-9) obtained in Production Examples 1-6 to 1-9 were used as binder resins, respectively.

I _S of the obtained binder resin was measured in the same manner as in the above (1).

Further, various characteristics of the negative electrode slurry composition using each binder resin, the electrode (negative electrode) manufactured using the negative electrode slurry composition, and the secondary battery manufactured using the electrode (negative electrode) were evaluated in the following order. The results are shown in Table 2.

(8) Preparation of slurry composition for negative electrode

100 parts by mass of a natural graphite anode active material (&quot; MPGC16 &quot;, manufactured by Mitsubishi Chemical Corporation) as an active material, 5 parts by mass of acetylene black (Denka Kogyo K.K., 2 parts by mass of the binder resin of 1-7 were mixed with 40 parts by mass of distilled water under the conditions of a rotation rate of 1000 rpm and a revolution of 2000 rpm using a self-propulsion type stirrer ("Awatolian Teraro" manufactured by Thinky Co.) to prepare a negative electrode slurry composition did.

(9) Evaluation of tin-plasticity of slurry composition for negative electrode

? _0.1 /? ₈₀ of the binder resin was obtained in the same manner as in (3) above, except that the negative electrode slurry prepared in (8) above was used.

(10) Preparation of electrode (cathode)

The slurry composition for negative electrode prepared in (8) above was coated on a copper foil (19 cm x 25 cm, thickness 20 m) using a doctor blade, dried in a circulating hot air dryer at 80 ° C for 1 hour, To obtain an electrode (negative electrode) comprising a copper foil coated with a mixed layer having a thickness of 80 mu m by drying under reduced pressure at 100 DEG C for 12 hours.

(11) Evaluation of uniformity of the mixed layer

The uniformity of the mixed layer was evaluated in the same manner as in (5), except that the electrode (cathode) prepared in (10) above was used.

(12) Secondary battery (2016 type coin battery)

A commercially available metal lithium electrode (positive electrode) and the electrode (negative electrode) prepared in (10) were opposed to each other with a separator (trade name: CELLGARD # 2400) interposed therebetween. A 2016 type coin cell was prepared using a 1M lithium hexafluorophosphate solution in which a mixture of ethylene carbonate / diethyl carbonate = 1/2 (volume ratio) was used as a nonaqueous electrolyte as a solvent.

(13) Measurement of initial battery capacity of secondary battery

(Current capacity: 0.6 mA / g-active material) at a charging / discharging rate of 0.5 C at 60 캜 and immediately after the preparation of the 2016-type coin battery manufactured by the above-mentioned method (12) And the measured value was used as the initial battery capacity.

As shown in the results of Table 2, the binder resins of Examples 1-4 to 1-7 had a large value of I _S , and as a result, the obtained negative electrode slurry composition had good tin firing. The better the tic baking of the slurry composition, the better the storage stability of the slurry composition and the uniformity of the mix layer, and the battery characteristics are improved. Actually, the electrode (negative electrode) obtained by using the slurry composition for a negative electrode in each of Examples had a good uniformity of the mixed layer. In addition, the initial battery capacity of the secondary battery using the electrode (negative electrode) was also good.

&Lt; Preparation Example 2-1: Preparation of polymer (B-1) >

A monomer aqueous solution obtained by mixing 29.1 parts by mass of N-vinylformamide, 0.9 parts by mass of methyl acrylate and 1.5 parts by mass of sodium acetate with respect to 70 parts by mass of deionized water was adjusted to pH = 6.3 by using phosphoric acid, .

The monomer control solution was cooled to 5 占 폚, placed in an adiabatic reaction vessel equipped with a thermometer, and subjected to nitrogen aeration for 15 minutes. Thereafter, 10 mass% of 1,500 ppm (large monomer) of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (VA-057 manufactured by Wako Pure Chemical Industries, (Monomer) as a 10 mass% aqueous solution, and further adding 200 ppm (a large monomer) of sodium hydrogen sulfite as a 10 mass% aqueous solution.

After the inside temperature exceeded the peak, the mixture was further aged for one hour, and the gel was taken out, pulverized with a meat chopper, dried at 60 DEG C for 10 hours, and the obtained solid was pulverized to obtain a powdery polymer. This is referred to as polymer (B-1).

&Lt; Preparation Example 2-2: Preparation of polymer (B-2) >

As a monomer, 27.0 parts by mass of N-vinylformamide and 3.0 parts by mass of methyl acrylate were used in the same manner as in Production Example 2-1 to obtain a powdery polymer. This is referred to as polymer (B-2).

&Lt; Preparation Example 2-3: Preparation of Polymer (B-3) >

A polymer was obtained in the same manner as in Production Example 2-1, except that 25.5 parts by mass of N-vinylformamide and 4.5 parts by mass of methyl acrylate were used as monomers. This is referred to as polymer (B-3).

&Lt; Preparation Example 2-4: Preparation of polymer (B-4) >

As a monomer, 24 parts by mass of N-vinylformamide and 6.0 parts by mass of methyl acrylate were used in the same manner as in Production Example 2-1 to obtain a powdery polymer. This is referred to as polymer (B-4).

&Lt; Preparation Example 2-5: Preparation of polymer (B-5) >

28.5 parts by mass of N-vinylformamide and 1.5 parts by mass of acrylic acid added with aqueous solution of lithium hydroxide until pH = 9 were used instead of methyl acrylate as the monomer, and the same procedures as in Production Example 2-1 were carried out To obtain a powdery polymer. This is referred to as polymer (B-5).

&Lt; Preparation Example 2-6: Preparation of polymer (B-6) >

27.0 parts by mass of N-vinylformamide and 3.0 parts by mass of acrylic acid with an aqueous lithium hydroxide solution until pH = 9 were used as the monomer without using methyl acrylate. To obtain a powdery polymer. This is referred to as polymer (B-6).

&Lt; Preparation Example 2-7: Preparation of polymer (B-7) >

As a monomer, 21.0 parts by mass of N-vinylformamide and 9.0 parts by mass of 2-methoxyethyl acrylate were used in the same manner as in Production Example 2-1 except that methyl acrylate was not used, . This is referred to as polymer (B-7).

&Lt; Preparation Example 2-8: Preparation of polymer (B-8) >

As a monomer, 18.0 parts by mass of N-vinylformamide and 12.0 parts by mass of 2-methoxyethyl acrylate were used in the same manner as in Production Example 2-1 except that methyl acrylate was not used, . This is referred to as polymer (B-8).

&Lt; Preparation Example 2-9: Preparation of polymer (B-9) >

Except that methyl acrylate was not used as the monomer, 29.1 parts by mass of N-vinylformamide and 0.9 parts by mass of methoxypolyethylene glycol monomethacrylate ("Blemmer PME-200" manufactured by Nichiyu Co., Ltd.) , And the procedure of Production Example 2-1 was carried out to obtain a powdery polymer. This is referred to as polymer (B-9).

&Lt; Preparation Example 2-10: Preparation of polymer (B-10) >

Except that methyl acrylate was not used and 28.5 parts by mass of N-vinylformamide and 1.5 parts by mass of methoxypolyethylene glycol monomethacrylate ("Blemmer PME-200" manufactured by Nichiyu Co., Ltd.) were used as the monomers , And the procedure of Production Example 2-1 was carried out to obtain a powdery polymer. This is referred to as polymer (B-10).

&Lt; Preparation Example 2-11: Preparation of polymer (B-11) >

As a monomer, 30.0 parts by mass of N-vinylformamide was used instead of methyl acrylate, and in place of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] Except that 0.88 mass% (a large monomer) of an azo-based polymerization initiator ("VPE-0201" manufactured by Wako Pure Chemical Industries, Ltd.) containing polyethylene glycol units was used as a polymerization initiator. To obtain a polymer. This is referred to as polymer (B-11).

&Lt; Preparation Example 2-12: Preparation of polymer (B-12) >

As a monomer, 28.5 parts by mass of N-vinylformamide and 1.5 parts by mass of methoxypolyethylene glycol monomethacrylate ("Blemmer PME-200" manufactured by Nichiyu Co., Ltd.) were used without using methyl acrylate, and 2 Azo polymerization initiator ("VPE-0201" manufactured by Wako Pure Chemical Industries, Ltd.) containing a polyethylene glycol unit was used instead of 2'-azobis [N- (2-carboxyethyl) A polymer in powder form was obtained in the same manner as in Production Example 2-1, except that 0.88 mass% (a large monomer) was used. This is referred to as polymer (B-12).

&Lt; Preparation example 2-13: Preparation of polymer (B-13) >

Except that methyl acrylate was not used and 27.0 parts by mass of N-vinylformamide and 3.0 parts by mass of methoxypolyethylene glycol # 550 acrylate ("AM-130G" manufactured by Shin-Nakamura Chemical Co., Ltd.) , And the procedure of Production Example 2-1 was carried out to obtain a powdery polymer. This is referred to as polymer (B-13).

&Lt; Preparation Example 2-14: Preparation of polymer (B-14) >

As the monomer, 27.0 parts by mass of N-vinylformamide, 2.1 parts by mass of methyl acrylate, and 0.9 parts by mass of acrylic acid with aqueous lithium hydroxide solution until pH = 9 were used, To obtain a powdery polymer. This is referred to as polymer (B-14).

&Lt; Preparation Example 2-15: Preparation of Polymer (B-15) >

As the monomer, 18.0 parts by mass of N-vinylformamide, 10.5 parts by mass of methyl acrylate, and 1.5 parts by mass of acrylic acid added with aqueous solution of lithium hydroxide until pH = 9 were used, To obtain a powdery polymer. This is referred to as polymer (B-15).

&Lt; Preparation Example 2-16: Preparation of polymer (B-16) >

As the monomer, 18.0 parts by mass of N-vinylformamide, 8.4 parts by mass of methyl acrylate, and 3.6 parts by mass of acrylic acid with an aqueous solution of lithium hydroxide until pH = 9 were used, To obtain a powdery polymer. This is referred to as polymer (B-16).

&Lt; Preparation Example 2-17: Preparation of polymer (B-17) >

As a monomer, methyl acrylate was not used, 9.0 parts by mass of N-vinylformamide, 16.5 parts by mass of 2-methoxyethyl acrylate and 4.5 parts by mass of acrylic acid added with aqueous solution of lithium hydroxide until pH = 9 The procedure of Production Example 2-1 was otherwise carried out to obtain a powdery polymer. This is referred to as polymer (B-17).

&Lt; Preparation Example 2-18: Preparation of Polymer (B-18) >

The procedure of Production Example 2-1 was repeated except that methyl acrylate was not used as the monomer and 28.5 parts by mass of N-vinylformamide and 1.5 parts by mass of N-vinyl-2-pyrrolidone were used, To obtain a polymer. This is referred to as polymer (B-18).

Production Example 2-19: Production of Polymer (B-19)

Except that methyl acrylate was not used as the monomer and 27.0 parts by mass of N-vinylformamide and 3.0 parts by mass of N-vinyl-2-pyrrolidone were used as the monomers, To obtain a polymer. This is referred to as polymer (B-19).

&Lt; Preparation Example 2-20: Preparation of polymer (B-20) >

A polymer was obtained in the same manner as in Production Example 2-1 except that methyl acrylate was not used as the monomer and only 30.0 parts by mass of N-vinylformamide was used. This is referred to as polymer (B-20).

[Examples 2-1 to 2-19 and Comparative Example 2-1]

The polymers (B-1) to (B-20) obtained in Production Examples 2-1 to 2-19 were used as binder resins, respectively.

Various characteristics of a slurry composition for a positive electrode using each binder resin, an electrode (positive electrode) produced using the slurry composition for the positive electrode, and a secondary battery manufactured using the electrode (positive electrode) were evaluated in the following order. The results are shown in Table 3.

(14) Preparation of slurry composition for positive electrode

0.06 g of the binder resin of Examples 2-1 to 2-19 and Comparative Example 2-1 and 2.0 g of water were dispersed using a self-propulsive stirrer (Thinky Co., "Awatolian Taro") at 1000 rpm, Kneaded under the conditions. To this, 3.0 g of lithium cobalt oxide ("CELSED C-5H" manufactured by Nippon Chemical Industry Co., Ltd.) was added and further kneaded by a self-propelled stirrer. To this, 0.15 g of acetylene black (manufactured by Denki Kagaku Kogyo K.K.) was further added and kneaded, followed by adjustment to water viscosity to prepare a slurry composition for positive electrode.

(15) Evaluation of dispersibility

The state of the slurry composition for a positive electrode prepared in (14) above was visually observed, and the dispersibility was evaluated according to the following evaluation criteria. On the other hand, evaluation of the dispersibility was performed only in Examples 2-18, 2-19 and Comparative Example 2-1.

?: Aggregation of the contents of the slurry composition for positive electrode was not confirmed.

X: Aggregation of the contents of the slurry composition for positive electrode was confirmed.

(16) Production of electrode (anode)

The slurry composition for positive electrode prepared in (14) above was coated on an aluminum foil (19 cm x 25 cm, thickness 20 m) using a doctor blade and dried on a hot plate at 100 캜 for 10 minutes. And further dried under reduced pressure of 0.6 kPa at 100 캜 for 12 hours by a vacuum drier to obtain an electrode (anode) in which a mixed layer having a film thickness shown in Table 3 was formed on a current collector (aluminum foil). Further, an electrode (anode) having an electrode density of 3 g / cm ³ was obtained by pressing at 100 캜 with a nip roll press (linear pressure: about 150 kgF / cm).

(17) Evaluation of flexibility

The electrode (positive electrode) after pressing as prepared in (16) was cut to a width of 3 cm and a length of 5 cm to obtain a test piece 2-1. Subsequently, mandrels (diameter of 10 mm, 8 mm, 6 mm, and 5 mm, respectively) were placed on the aluminum foil of the test piece 2-1, and one side of the test piece 2-1 was fixed with a tape. The state of the mixture layer when the test piece 2-1 was bent so that the aluminum foil surface was in the inside of the humidity of 10% or less was magnified and observed with a microscope 60 times, and the flexibility of the electrode was evaluated according to the following evaluation criteria.

○: No change.

B: Horizontal stripes entered.

X: Cracks or peeling occurred.

(18) Measurement of peel strength

The electrode (positive electrode) after pressing as prepared in (16) above was cut to a width of 30 mm to obtain a test piece 2-2. Using a Borazon cutting edge (rake angle 20 deg., Clearance angle 10 deg., Cutting edge angle 60 deg.) With a width of 1 mm, an initial pressing load of 0.5 N, The balance load was 0.3? 0.2N, the horizontal velocity was 1 占 퐉 / sec, the vertical velocity was 0.2 占 퐉 / sec, and the initial contact load was 0.08 to 1N. The maximum stress value at the time when the boron zone cutting edge moved on the interface between the alloy layer and the aluminum foil was recorded as three points. The average value of the maximum stress values was taken as the peeling strength between the mixture layer and the current collector. The larger this value is, the more the mixed layer is firmly adhered to the current collector.

On the other hand, the peeling strength was measured only in Examples 2-1 to 2-8, 2-14 to 2-19 and Comparative Example 2-1.

(B-1) to (B-17) having the structural unit represented by the formula (1) and the structural unit represented by the formula (2) and / or the formula (3) (B-18) and (B-19) having the structural units derived from the binder resin of Examples 2-1 to 2-17, the structural unit represented by the formula (1) and the compound represented by the formula (31) (Positive electrode) excellent in flexibility was obtained from the binder resins of Examples 2-18 and 2-19.

Particularly, the polymers (B-5) and (B-6) obtained by copolymerizing N-vinylformamide with acrylic acid neutralized with lithium hydroxide and the polymers (B- 17, 17, 17, 18, 19, 20, 21, 21, 22, and 23 were excellent in binding property.

From the binder resins of Examples 2-18 and 2-19 comprising any one of the polymers (B-18) and (B-19) having a structural unit derived from the compound represented by the formula (31) A good slurry composition was obtained.

On the other hand, in Comparative Example 2-1 comprising a polymer (B-20) having neither the structural unit represented by the formula (2), the structural unit represented by the formula (3), or the structural unit derived from the compound represented by the formula The electrode (anode) obtained from the binder resin had poor flexibility as compared with the electrodes (anode) of Examples 2-1 to 2-19.

&Lt; Production example 3-1 >

30 parts by mass of N-vinylformamide (molecular weight: 71.08) was added to 70 parts by mass of deionized water to adjust the pH to 6.3 with phosphoric acid to obtain a monomer control solution.

The monomer control solution was cooled to 5 占 폚, placed in an adiabatic reaction vessel equipped with a thermometer, and subjected to nitrogen aeration for 15 minutes. Thereafter, 0.4 mass parts of an aqueous solution of 10 mass% of 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] (manufactured by Wako Pure Chemical Industries, Ltd., "VA-057" , Followed by 0.1 part by mass of a 10 mass% aqueous solution of t-butyl hydroperoxide and a 10 mass% aqueous solution of sodium hydrogensulfite, respectively, to perform polymerization.

After the inner temperature had exceeded the peak, the gel was further aged for one hour, and the gel was taken out and pulverized with a meat chopper, followed by drying at 60 DEG C for 10 hours. The resulting solid was pulverized to obtain a powdery N-vinylformamide polymer (polymer ).

Subsequently, 4 parts by mass of the obtained N-vinylformamide polymer was dissolved in 90 parts by mass of deionized water to prepare a polymer aqueous solution.

Separately, 11.8 parts by mass of lithium hydroxide monohydrate (molecular weight 42) in which the molar ratio with respect to the N-vinylformamide polymer was 50% was dissolved in 6 parts by mass of deionized water to prepare an aqueous solution of lithium hydroxide monohydrate.

An aqueous solution of lithium hydroxide monohydrate was added to the aqueous polymer solution, stirred uniformly, and heated at 75 占 폚 for 5 hours to carry out a hydrolysis reaction. The reaction solution after the hydrolysis reaction was cooled to obtain an aqueous solution of the binder resin? -1 (binder resin aqueous solution? -1).

(Measurement of Content Ratio of Constituent Unit)

The content of the structural unit represented by the formula (21) in the binder resin was measured by the following colloid titration method.

The binder resin aqueous solution was quenched and collected in a measuring flask, to which demineralized water was added. The aqueous solution was collected from the measuring flask with a hole pipette, and then added with demineralized water. The pH was adjusted to pH 2.5 with a 1N-hydrochloric acid solution while checking with a pH meter.

To the obtained test solution, toluidine blue was added and titrated with N / 400-polyvinylsulfate potassium solution ("PVSK" manufactured by Wako Pure Chemical Industries, Ltd.). The point where the test liquid discolored from blue to purple was regarded as the end point. From the titration results, the content ratio of the structural unit represented by the above formula (21) was determined. The results are shown in Table 4.

In Table 4, &quot; unit (21) &quot; is the structural unit represented by the above formula (21).

The content of the structural units represented by the above formulas (22) and (23) in the binder resin was determined by the following ¹³ C-NMR measurement.

15 mg of a powder of the binder resin obtained by freeze-drying an aqueous solution of the binder resin was dissolved in 900 mg of water containing 0.5% by mass of sodium 3- (trimethylsilyl) -1-propanesulfonate as a reference material. This solution was placed in a test tube having a diameter of 5 mmφ so as to have a liquid height of about 5 cm and analyzed using a nuclear magnetic resonance apparatus (Agilent Technologies Inc., "Varian Inova 500 type FT-NMR") under the following conditions Respectively.

· Observation frequency: 500 MHz (1H decoupling pulse mode)

· Measuring temperature: 30 ℃

· Number of accumulation: 10,000 times

On the other hand, in the Fourier transform of the FID signal, after the zero filling was performed twice, the broadening factor was set to 10 Hz.

In the obtained ¹³ C-NMR spectrum, the signal intensity at 160 to 165 ppm was regarded as the structural unit represented by the chemical formula 22, the signal intensity at 150 to 155 ppm was regarded as the structural unit represented by the chemical formula 23, The content ratio of the structural units represented by the above formulas (22) and (23) in the structural unit other than the structural unit represented by the above-mentioned formula (21) was obtained. The results are shown in Table 4.

In Table 4, &quot; unit (22) &quot; means the structural unit represented by the above-mentioned chemical formula 22 and &quot; unit (23) &quot;

&Lt; Production example 3-2 &

Except that the amount of the lithium hydroxide monohydrate to be added was changed to 4.7 parts by mass (the amount by which the molar ratio with respect to the N-vinylformamide polymer was 20%) in the same manner as in Production Example 3-1. To obtain an aqueous solution (binder resin aqueous solution alpha-2).

The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin?-2. The results are shown in Table 4.

&Lt; Production Example 3-3 &

The same procedure as in Production Example 3-1 was repeated except that 11.2 parts by mass of sodium hydroxide (molecular weight: 40) (amount by which the molar ratio with respect to the N-vinylformamide polymer was 50%) was used instead of lithium hydroxide monohydrate, 3 (binder resin aqueous solution? -3).

The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin? -3. The results are shown in Table 4.

&Lt; Preparation Example 3-4 &

Except that sodium hydroxide (molecular weight: 40) was used in place of lithium hydroxide monohydrate and the amount of sodium hydroxide added was changed to 33.7 parts by mass (amount by which the molar ratio with respect to the N-vinylformamide polymer was 150%) , An aqueous solution of the binder resin? 1-4 (binder resin aqueous solution? 1-4) was obtained in the same manner as in Production Example 3-1.

The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin (1-4). The results are shown in Table 4.

Separately, 4 parts by mass of the N-vinylformamide polymer was dissolved in 96 parts by mass of deionized water to obtain an aqueous polymer solution, thereby obtaining an aqueous solution (binder resin aqueous solution? 2-4) of the binder resin? 2-4.

The binder resin aqueous solution β1-4 and the binder resin aqueous solution β2-4 were mixed in a ratio such that the molar ratio of the binder resin β 1-4 and the binder resin β2-4 was 50:50 and this was mixed with an aqueous solution of the binder resin β- Resin aqueous solution β-4).

<Production Example 3-5>

5 was obtained in the same manner as in Production Example 3-1 except that the amount of lithium hydroxide monohydrate added was changed to 1.2 parts by mass (amount by which the molar ratio with respect to the N-vinylformamide polymer was 5%) of the binder resin? To obtain an aqueous solution (binder resin aqueous solution? -5).

The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin?-5. The results are shown in Table 4.

<Production Example 3-6>

The neutralization treatment was carried out using a 1N nitric acid aqueous solution so that the pH of the binder resin aqueous solution? -2 obtained in Production Example 3-2 was 6.5. The aqueous solution obtained by the neutralization treatment was used as an aqueous solution of the binder resin? -6 (binder resin aqueous solution? -6).

 The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin? -6. The results are shown in Table 4.

&Lt; Preparation Example 3-7 &

And 3 parts by mass of N-vinyl acetamide polymer (molecular weight 85.10) were dissolved in 90 parts by mass of deionized water to prepare an aqueous polymer solution.

Separately, 7.0 parts by mass of lithium hydroxide monohydrate (molecular weight 42) in an amount such that the molar ratio with respect to the N-vinyl acetamide polymer was 150% was dissolved in 7 parts by mass of deionized water to prepare an aqueous solution of lithium hydroxide monohydrate.

An aqueous solution of lithium hydroxide monohydrate was added to the aqueous polymer solution, stirred uniformly, and then heated at 90 占 폚 for 15 hours to carry out a hydrolysis reaction. The reaction solution after the hydrolysis reaction was cooled to obtain an aqueous solution of the binder resin? -7 (binder resin aqueous solution? -7).

The content of the structural units represented by the above formulas (21) to (23) was determined for the obtained binder resin? -7. The results are shown in Table 4.

&Lt; Preparation Example 3-8 &

4 parts by mass of N-vinylformamide polymer was dissolved in 96 parts by mass of deionized water to obtain an aqueous polymer solution, which was used as an aqueous solution (binder resin aqueous solution? 2-8) of the binder resin? 2-8.

Table 4 shows the content ratios of the structural units represented by the above formulas (21) to (23) in the obtained binder resin? 2-8.

The binder resin?-1 obtained in Production Example 3-1 had a structure in which 42 mol% of the structural unit represented by the formula (21) (wherein R ²¹ in the formula (21) is a hydrogen atom), the structural unit represented by the formula , 47 mol% of R ²² and R ²³ in the formula (22) are hydrogen atoms), 11 mol% of the structural unit represented by the formula (23) (provided that R ²⁴ and R ²⁵ in the formula (23) (Corresponding to the polymer (?)).

The binder resin? -2 obtained in Production Example 3-2 contained 19 mol% of the structural unit represented by the formula (21) (R ²¹ in the formula (21) is a hydrogen atom), the structural unit represented by the formula With the proviso that R ²² and R ²³ in the formula (22) are hydrogen atoms), 3 mol% of the structural unit represented by the formula (23) (provided that R ²⁴ and R ²⁵ in the formula (23) (Corresponding to the polymer (?)).

The binder resin? -3 obtained in Production Example 3-3 contained 42 mol% of the structural unit represented by the formula (21) (R ²¹ in the formula (21) is a hydrogen atom), the structural unit represented by the formula With the proviso that R ²² and R ²³ in the formula (22) are hydrogen atoms) and 12 mol% of the structural unit represented by the formula (23) (provided that R ²⁴ and R ²⁵ in the formula (23) are hydrogen atoms) (Corresponding to the polymer (?)).

The binder resin? 1-4 obtained in Production Example 3-4 was a polymer (corresponding to polymer (? 1)) containing 95 mol% of the structural unit represented by the above formula (21) in which R ²¹ is a hydrogen atom. Respectively. The binder resin β-4 is a mixture of the binder resin β1-4 (corresponding to the polymer (β1)) and the structural unit represented by the formula 22 (provided that R ²² and R ²³ in the formula 22 are hydrogen atoms) (Corresponding to the polymer (? 2)).

The binder resin? -5 obtained in Production Example 3-5 was a copolymer of 5 mol% of the structural unit represented by the formula (21) (wherein R ²¹ in the formula (21) is a hydrogen atom), the structural unit represented by the formula With the proviso that R ²² and R ²³ in the formula (22) are hydrogen atoms) and 1 mol% of the structural unit represented by the formula (23) (wherein R ²⁴ and R ²⁵ in the formula (23) are hydrogen atoms) (Corresponding to the polymer (?)).

The binder resin? -6 obtained in Production Example 3-6 contained 19 mol% of the structural unit represented by the formula (21) (R ²¹ in the formula (21) is a hydrogen atom), the structural unit represented by the formula With the proviso that R ²² and R ²³ in the formula (22) are hydrogen atoms), 17 mol% of the structural unit represented by the formula (23) (provided that R ²⁴ and R ²⁵ in the formula (23) (Corresponding to the polymer (?)).

The binder resin? -7 obtained in Preparative Example 3-7 was a mixture of 11 mol% of the structural unit represented by the formula (21) (R ²¹ in the formula (21) is a hydrogen atom), the structural unit With the proviso that R ²² and R ²³ in the formula (22) are hydrogen atoms) (the polymer (?)).

The binder resin? 2-8 obtained in Preparative Example 3-8 was a polymer (polymer (? 2) having 100 mol% of the structural unit represented by the above-mentioned formula (22) in which R ²² and R ²³ in the formula (22) ).

On the other hand, the concentration of the binder resin in each of the binder resin aqueous solutions obtained in Production Examples 3-1 to 3-5 and 3-8 was 4% by mass, and the concentration of the binder resin in the aqueous binder resin solution obtained in Production Examples 3-6 and 3-7 The concentration is 3% by mass.

&Quot; Example 3-1 &quot;

&Lt; Preparation of slurry composition for negative electrode &

2.5 g of the binder resin aqueous solution α-1 and 5 g of a natural graphite-based negative electrode active material ("MPGC16" manufactured by Mitsubishi Chemical Co., Ltd.) were spin-coated at 1000 rpm using a self-propelled stirrer (" Lt; / RTI &gt; Thereafter, the slurry composition for a negative electrode was obtained by adjusting the viscosity to a coatable viscosity.

&Lt; Preparation of electrode (cathode) >

The obtained slurry composition for a negative electrode was coated on a copper foil (19 cm x 25 cm, thickness 20 m) using a doctor blade and dried at room temperature for 1 hour. And further dried under reduced pressure at 0.6 kPa and 60 캜 for 12 hours in a vacuum dryer to obtain an electrode (negative electrode) in which a mixed layer having a film thickness of 80 탆 was formed on a current collector (copper foil). Further, an electrode (cathode) having an electrode density of 1.5 g / cm &lt; ³ &gt; was obtained by pressing at 100 DEG C with a nip roll press (linear pressure: about 150 kgF / cm).

Separately, an electrode (negative electrode) in which a mixed layer having a film thickness of 50 μm was formed on a current collector (copper foil) was similarly prepared.

In the evaluation of the flexibility and binding property shown below, an electrode (negative electrode) having a mixture layer thickness of 80 m was used and an electrode (negative electrode) having a mixture layer thickness of 50 m was used for evaluating the battery characteristics.

<Evaluation>

(19) Evaluation of flexibility

The previously prepared electrode (negative electrode) after being pressed was cut to a width of 3 cm and a length of 5 cm to obtain a test piece 3-1. Subsequently, the mandrel (diameter: 16 mm, 10 mm, 8 mm, 5 mm, 3 mm, 2 mm, respectively) was placed on the copper foil of the test piece 3-1, and one side of the test piece 3-1 was fixed with a tape. The state of the mixed layer when the test piece 3-1 was bent so that the copper foil surface was in the inside of the humidity of 10% or less was observed with a microscope magnified by 60 times and the flexibility of the electrode was evaluated according to the following evaluation criteria. The results are shown in Table 5.

○: No change.

B: Horizontal stripes entered.

X: Cracks or peeling occurred.

(20) Evaluation of bondability

The electrode (cathode) after the pressing as previously prepared was cut so as to have a width of 20 mm and a length of 80 mm. The double-faced tape (# 570, manufactured by Sekisui Chemical Co., Ltd.) ) To a polycarbonate sheet (25 mm in width, 100 mm in length, and 1 mm in thickness) to obtain Test Specimen 3-2.

Test piece 3-2 was set on a tensile strength tester Tensilon tester ("RTC-1210A", manufactured by Orientec Co., Ltd.) and the copper foil was peeled 180 ° at 10 mm / The peel strength was measured. The results are shown in Table 5.

(21) Evaluation of battery characteristics

The previously prepared electrode (negative electrode) after pressing was opposed to a commercially available metallic lithium electrode (positive electrode) with a separator (Cell Guard # 2400) interposed therebetween. A 2032-type coin cell was prepared using a 1M lithium hexafluorophosphate solution in which a mixture of ethylene carbonate / diethyl carbonate = 1/2 (volume ratio) was used as a nonaqueous electrolyte as a solvent.

The resulting 2032-type coin cell was charged and discharged at 0 V at a charging / discharging rate of 0.5 C at 60 ° C under a constant-current method (current density: 0.6 mA / g-active material) , The battery capacity in the first cycle, and the battery capacity in the 30th cycle were measured. The ratio of the battery capacity at the 30th cycle to the battery capacity at the first cycle was expressed as a percentage, and the battery characteristics were evaluated based on the following evaluation criteria as the battery capacity retention ratio. The results are shown in Table 5.

○: Battery capacity retention rate is 80% or more.

X: Battery capacity retention rate is less than 80%.

[Examples 3-2 to 3-6, Reference Example 3-7, Comparative Example 3-1]

The amount of the binder resin aqueous solution was changed as shown in Table 5 and the amount of the binder resin aqueous solution was changed to 2.5 g,? -6,? -7 (Negative electrode) and a 2032-type coin battery were produced and evaluated in the same manner as in Example 3-1, The results are shown in Table 5.

&Quot; Example 3-8 &quot;

&Lt; Preparation of slurry composition for positive electrode &

1.5 g of the binder resin aqueous solution? -5 and 2.0 g of water were kneaded using a self-propulsive stirrer ("Awatolirentero" manufactured by Thinky Co., Ltd.) at a revolution of 1000 rpm and a revolution of 2000 rpm. To this, 3.0 g of lithium cobalt oxide ("Celsid C-5H" manufactured by Nippon Chemical Industry Co., Ltd.) was added and further kneaded by a self-propelled stirrer. 0.12 g of acetylene black (manufactured by Denki Kagaku Kogyo K.K.) was further added thereto, followed by kneading, and then adjusted to a coating viscosity to prepare a positive electrode slurry composition.

&Lt; Preparation of electrode (positive electrode) >

The obtained slurry composition for a cathode was coated on an aluminum foil (19 cm x 25 cm, thickness 20 m) using a doctor blade and dried at room temperature for 1 hour. And further dried under reduced pressure at 0.6 kPa and at 60 캜 for 12 hours in a vacuum dryer to obtain an electrode (anode) in which a mixed layer having a film thickness of 80 탆 was formed on a current collector (aluminum foil). Further, an electrode (anode) having an electrode density of 3 g / cm ³ was obtained by pressing at 100 캜 with a nip roll press (linear pressure: about 150 kgF / cm).

Separately, an electrode (positive electrode) in which a mixture layer having a film thickness of 50 m was formed on a current collector (aluminum foil) was similarly prepared.

In the evaluation of the flexibility and binding property shown below, an electrode (positive electrode) having a mixed layer thickness of 80 m was used, and an electrode (positive electrode) having a mixed layer thickness of 50 m was used for evaluation of battery characteristics.

<Evaluation>

(22) Evaluation of flexibility

The previously prepared electrode (positive electrode) after being pressed was cut to a width of 3 cm and a length of 5 cm to obtain Test Specimen 3-3. The flexibility of the electrode was evaluated in the same manner as in (19) above, except that the test piece 3-3 was used. The results are shown in Table 5.

(23) Evaluation of bondability

The prepared electrode (anode) was cut to a width of 20 mm and a length of 80 mm. The mixture layer side of the cut pieces was coated with a polycarbonate sheet (25 mm in width, 100 mm in length, 1 mm in thickness) to obtain Test Specimen 3-4.

The peel strength was measured in the same manner as in (20) except that the above-mentioned Test Specimen 3-4 was used. The results are shown in Table 5.

(24) Evaluation of battery characteristics

A commercially available metal lithium electrode (negative electrode) and the previously prepared electrode (positive electrode) were opposed to each other with a separator (Cell Guard # 2400) interposed therebetween. A 2032-type coin cell was prepared using a 1M lithium hexafluorophosphate solution in which a mixture of ethylene carbonate / diethyl carbonate = 1/2 (volume ratio) was used as a nonaqueous electrolyte as a solvent.

The battery characteristics were evaluated in the same manner as in (21), except that the obtained 2032-type coin cell was used. The results are shown in Table 5.

As shown in the results of Table 5, the binder resins α-1 to α-3, α-5 to α-7 and the binder resins α-1 to α-3 comprising the polymer having the structural units represented by the above formulas 21 and 22 (corresponding to the polymer (Corresponding to the polymer (? 1)) containing 95 mol% of the structural unit represented by the formula (21) and a polymer having 100 mol% of the structural unit represented by the formula (22) In the case of Examples 3-1 to 3-8 using the binder resin beta-4, cracks and the like were not observed even in mandrel testing of a diameter of 5 mm, and good results were obtained. Particularly, in Example 3-4 using the binder resin? -4, no cracks or the like were found even in a mandrel test with a diameter of 2 mm.

In addition, the binder resins α-1 to α-3, α-5 to α-7, and the binder resin β-4 were excellent in adhesion and batteries with high battery capacity retention rates were obtained.

On the other hand, in Comparative Example 3-1 using the binder resin? 2-8 comprising a polymer having 100 mol% of the structural unit represented by the formula (22) (corresponding to the polymer (? 2)), the structural unit represented by the formula Because it does not contain, cracks were seen in mandrel test of diameter 8mm.

The binder resin? 2-8 had insufficient binding property to the current collecting foil and the peel strength was lower than that of the binder resins? -1 to? -3,? -5 to? -7 and the binder resin? -4 .

From these results, it is assumed that if an electrode is manufactured using the binder resin? 2-8, problems such as cracking and peeling also occur in the production line.

According to the binder resin for a nonaqueous secondary battery electrode of the first aspect of the present invention, when mixed with an active material and water, a slurry composition having good tic-firing can be obtained, and further, it can be distributed in powder form.

 The slurry composition for a nonaqueous secondary battery electrode of the first aspect of the present invention is obtained by using the binder resin for a nonaqueous secondary battery electrode of the first aspect and has good tin firing. Therefore, the slurry composition for a nonaqueous secondary battery electrode of the first aspect of the present invention has good storage stability. By using the slurry composition for a nonaqueous secondary battery electrode of the first aspect of the present invention, an electrode for a nonaqueous secondary battery in which a composite layer having good uniformity and adhesion to the current collector (binding property) is formed on the current collector is obtained .

The electrode for a non-secondary battery according to the first aspect of the present invention is favorable in uniformity of the compounded layer and adhesion (binding property) with the current collector. Therefore, according to the nonaqueous secondary battery having the electrode, good battery characteristics can be obtained.

According to the binder resin for a non-aqueous secondary battery electrode of the second and third aspects of the present invention, an electrode for a non-aqueous secondary battery excellent in flexibility can be formed.

According to the binder resin composition for a nonaqueous secondary battery electrode of the second and third aspects of the present invention, an electrode for a non-aqueous secondary battery excellent in flexibility can be formed.

The slurry composition for a nonaqueous secondary battery electrode according to the second and third aspects of the present invention is obtained by using the binder resin for a nonaqueous secondary battery electrode or the binder resin composition for a nonaqueous secondary battery electrode of the second and third aspects, An electrode for a non-aqueous secondary battery excellent in flexibility can be obtained.

The non-aqueous secondary battery electrode of the second and third aspects of the present invention is excellent in flexibility. Therefore, according to the nonaqueous secondary battery having the electrode, good battery characteristics can be obtained.

Claims (13)

(a) a structural unit represented by the following general formula (11)
(b) a structural unit derived from a compound represented by the following general formula (31)
And a polymer (B) having a repeating unit represented by the following formula (1).
(11)

(In the formula (11), R ¹¹ and R ¹² are each independently a hydrogen atom.)
(31)

(Wherein R ³¹ and R ³² are each independently a divalent substituent, R ³³ is a monovalent substituent, and any of R ³¹ to R ³³ has a vinyl group structure, s and t are each independently 0 Or 1). delete delete delete delete A binder resin for a non-aqueous secondary battery electrode, which contains the following component (?), Component (?) Or all of these components.
(?) Component (?) having a structural unit represented by the following formula (21) and a structural unit represented by the following formula (22).
(?): A mixture of a polymer (? 1) having a structural unit represented by the following formula (21) and a polymer (? 2) having a structural unit represented by the following formula (22).
[Chemical Formula 21]

(In the formula (21), R ²¹ is a hydrogen atom.)
[Chemical Formula 22]

(In the formula (22), R ²² and R ²³ are each a hydrogen atom.) The method according to claim 6,
Wherein at least one of the polymer (?), The polymer (? 1) and the polymer (? 2) has a structural unit represented by the following formula (23).
(23)

(In the formula (23), R ²⁴ and R ²⁵ are each a hydrogen atom.) 8. The method according to claim 6 or 7,
Wherein the binder resin for a non-aqueous secondary battery electrode is obtained by hydrolyzing the polymer (? 2). A binder resin composition for a nonaqueous secondary battery electrode, which comprises the binder resin for a nonaqueous secondary battery electrode according to any one of claims 1, 6, and 7. A binder resin composition comprising the binder resin for a non-aqueous secondary battery electrode according to any one of claims 1 to 7, or a binder resin composition for a non-aqueous secondary battery electrode comprising the binder resin, an active material, A slurry composition for a nonaqueous secondary battery electrode. A current collector, and a mixture layer provided on the current collector,
The binder resin composition for a non-aqueous secondary battery electrode according to any one of claims 1, 6, and 7, or a binder resin composition for a non-aqueous secondary battery electrode comprising the binder resin, Wherein the non-aqueous secondary battery comprises: A current collector, and a mixture layer provided on the current collector,
Wherein the mixed layer is obtained by coating the current collector with the slurry composition for a nonaqueous secondary battery electrode according to claim 10 and drying the mixture. A nonaqueous secondary battery comprising the electrode for a nonaqueous secondary battery according to claim 11.